Odorheiu Secuiesc (Székelyudvarhely) and its environs have been inhabited since ancient times.
This fact is proved by the finds which have been excavated in this area, such as stone tools, stone blades, stone chisels, pottery from the Neothic era, polished axes, bronze axes sickles, and objects belonging to the early Iron Age.
On the rocky hills of Budvár there used to be a fortress during the late Iron Age (Le Téne), but the settlement was at the foot of the hill.
Later on, probably in the 2nd c., on the place where the ruins of the Székely Támadt fortress can be found today, there was established a Roman castrum (military camp).
Its inhabitans must have been the soldiers of Cohors I. Ubiorum and Cohors IV. Britanica.
The bath of the Roman civil settlement was excavated at the end of the last century by the teachers Téglás Gábor and Solymossy Endre.

In order to secure the eastern boundaries, the Hungarian monarchy had organized the defendance of the region long before the Szeklers from Udvarhely (telegdi) were settled here.
The new fortress built on the Budvár and the pottery finds belonging to the 11th and 12th c., which were dug out in 1956 not far from the centre of the town, prove this thing.
The Szeklers from Udvarhely (telegdi) are firts mentioned in the document in 1224.
The name of the town was for the first time in the papal register for duties, in 1333 (in it, it is mentioned the priest of the settlement, called Stephanus, who had paid a duty of seven denarius).
The only monument which remained from this period is the Jesus Chapel, which can be found at the edge of the town on the left side of the road to Segesvár.

The market-town Odorheiu Secuiesc (Székelyudvarhely) was used under the name of "Opido Wdvarhel" in a document issued on 12th August 1485 in Medgyes by the Transylvanian voivode and Szekler bailiff Báthori István.
We don't know when it got this title.
Jakab Elek just supposes that "it must have be given by the king Zsigmond"- but, he himself remarks that there is no evidence of the fact.

The first know charter was given to the town by queen Izabella on 30th November 1557, exempting the town from any kind of duty, excepting the which was to be paid to the Turkish sultan.
Later, in a letter dated on 10th November 1558, the queen takes the town out of the authority of the Chair of Odorhei (district "Szék") and puts it under the rule of their own royal judge.
This is the first source which provides information about the judging forum.
In the same year queen Izabella donates to the market town Odorheiu Secuiesc (Székelyudvarhely) a seal whith the coat-of-arms.
This seal was described by Jakab Elek in the following way: "on a shield, having a blue background there is an armoured arm holding a dagger, the dagger pierces a heart and a bear head, (this is the ancient Szekler coat-of-arms).
In the upper side of the shield there are four stars and the inscription "The seal of the market town Odorheiu Secuiesc (Székelyudvarhely)" (Sigillum Oppidi Siculicalis Udvarhely).

The title of Szekely Mother Town, given to Székelyudvarhely raised many debates.
Lakatos István, a priest from Csíkkozmás, but who was born in Udvarhely, speaks about it in his manuscript which was finished in 1702.
He calls it "the capital of the entire Szekler Land". Later in the 18th c. (and not earlier) it comes into fashion beside the title of mother town.
By the beginning of the 19th c. we meet such denominations as Areopolisz or Szekler Athens.
It is undeniable that the District of Udvarhely (Udvarhelyszék), and not the town, bore the title of "mother district of the Szekler districts"-this is due to the fact that between the years 1505 and 1562 there existed a law court for appeal in Székelyudvarhely for the whole region.

At the beginning the settlement was rather small : it covered the area of today's downtown and its surroundings.
By the second half of the 16th c. it grows because of the moving in of the inhabitants of the annexed villages: Gyárosfalva (1571), Szentimrefalva (1577), Cibrefalva (1620).
The written sources of information preserved five street names and squares: the Piac (the today's centre), the Botos street (the today's Kossuth street), the Varga street (maybe the lower part of the Szentimre street), the Darabont street (the today's Bethlen Gábor street) and the Szentimre street.
Only one architectural monument remained from this period, unfortunately in ruins, that is Székely Támadt fortress.

The demographic situation of the town can be first appreciated in 1567 according to the list of the mounted knights and to the register of the 25 coins denarius which registered 54 gates (houses).
It is interesting to compare thes to the other towns: Targu Mures - 125, Targu Secuiesc - 60, Vlahita - 63, Miercurea-Ciuc - 16.
According to the muster from 1614 the structure of the population is the following: 5 noblemen, 30 mounted knights, 4 foot-soldiers, 20 servant, 115 families - that means 870 inhabitans.

The pricely period of Székelyudvarhely is determined by the development of the guides - this is also shown by the muster from 1614.
There are some people who say that the development of the guilds can be traced back to the 15th c., but the first attested testimony which was found in a tanner's guild-chest was from 1556.
The potter's guild was a probably established in 1572, but its status was recognized by the authorities only in 1613.
The locksmiths' guild and that of the sword-sharpeners' were established in 1613, and in 1630 that of the butchers' and in 1635 that of the boot-makers' who splitted off from the tanners', in 1638 the society of the merchants was founded.

Another important factor in the development of the town was the secondary school.
There were two secondary schools.
The first is the Jesuit school which had been functioning since 1593, later it became the Catholic high-school (the predecessor of the today's Tamási Áron high-school), founded by Marosvásárhelyi (Mészáros) Gergely.
The second was the Reformed College which was founded in 1670, (the today's Benedek Elek Teachers' Training School), founded by Bethlen János, the chancellor of the prince Apaffi Mihály).
Its rector was Letenyei Pál.

At the beginning of the 18th c. the town was tried by the wars and by the devastating plague (1708 - 1712, 1717 - 1720), but after all these its economy recovered again.
This is reflected by the Baroque monuments which were built: between 1712 and 1779 the Franciscan Church and Nunnery, the Reformed Church ( 1780 - 1781) and the Catholic Church (1787-1793).

Starting with the end of the 18th c. the guilds had their golden age.
Different guilds established their own organizations, such as : in 1779 the joiners, in 1803 the hatters, in early 1840's the saddlers, in 1856 the shoemakers, in 1862 the farmers, the carters and the carpenters.
The network of the streets was developed.
In a desciption of the town from 1826 there are mentioned the main streets, such as : the Szent Miklós street, on the place of today's Márton Áron Square, the Barátok street which was next to the Franciscan Nunnery, not far from the river Küküllő, the today's Tomcsa Sándor street was the former Cigány street.
In 1804 was roofed the market place where the tanners, the bootmakers, the potters and the butcers sold their goods.
In 1828-29 was built the old Town Hall.
Between 1817 and 1819 the main roads were paved and between 1828 and 1831 there were built 13 brick and stone, storeyed houses in the centre of the town respectively in the Botos, Bethlen and Szentimre street.

Naturally the embourgeoisement of the town had its unfavorable side too.
The people belonging to different social strata had to pay duty in different ways and this brought about a permanent tension.
In 1765 there was made a note about the shortcommings of the public sanitation: "Because of the lasting rainy weather the streets were covered with mud for months.
(...) The vagabondage during the nights, the drinking, the row, the noise of the gun-shots disturbed the peaceful citizens.
(The night-watchmen can't be found anywhere.) The butcher's shop are run by the butchers according to their will, the cows are slaughtered in the market place, in front of the Town Hall, and their blood pollutes the air during the summer." Several travelers from the beginning of the 19th c. say that there isn't rooms, there is no glass in the windows, and the bed-clothes are soiled.
But pubs are a lot.
Szigethi Gyula Mihály, the professor of the College wrote in 1826 that there are so many signboards that "a squirrel could leave the town" following these signboards.

The revolution from 1848-49 and the following totalitarian regime restrain the development of the town but around the 60's of the last century we can witness the advance of the embourgeoisement and urbanization.
In the 1870's, 23,42% of the population of Székelyudvarhely were craftsmen.
They were organized in associations continuing the tradition of the guilds even after 1872 when the guild system was officially liquidated.
In 1873 was established the first "Pawn-Borrowing House" (unfortunately with a little capital at the beginning).
In 1888 on 15th March was opened the railway between Héjasfalva and Székelyudvarhely, the first factories apeared, (in 1910 there were three of them).
The increasing cultural demands of the merchants and craftsmen are satisfied by different cultural societies and clubs such as: the Reading Club established in 1872, the Women Society (1875), the Reading Club of the Young Merchants (1887), the Self-educative, craft and assistance society (1890), Choral Society (later it becomes the Szekler Choral Society) (1868), Symphony Orchestra (1898).
In 1872 is edited the "Udvarhely", the first local newspaper edited by Szombathy Ignác.

The school network is enlarged too. In 1871 is established the Governamental Science School, in 1893 the Stone and Pottery Professional School.
New buildings are built downtown such as: the old hospital (1885), the new Town Hall (1897), the building of the Governamental Science School (1891), the Catholic High School (1910), the new building of the Reformed College (1912).
The town spreads on the other bank of the Küküllő river, towards Szombatfalva which is annexed to the town officially in 1895.

In 1896 Hankó Vilmos describes the town in the following way: "Its buildings, its streets and roads, the emerging church steeples among the storeyed houses, the lively life from the streets, give the impression of a developing, tidy town.
" It's true that there were other opinions too.
Szabó Dezső, the teacher of the Science High School wrote about Udvarhely, at the turn of the century: "Around a lot of stones three high schools and four churches grieve towards the sky.
On the stones some hundred Szekelers and some thousen dignified men hang around.
In the sky - clouds, in the air - rain, on one of the churches and old greenish-black flag, on the stones - mud.
This is Odorheiu Secuiesc (Székelyudvarhely) - the town of Gorkian moods and Rembrandt like paintings."

In spite of all thee we can say that the age of dualism represented the most dynamic period in the development of Odorheiu Secuiesc (Székelyudvarhely) urbanization of the town, which determined the today's look of the downtown.
Unfortunately this development of the town came to a deadlock at the level it reached at the turn of the century.
Between the two World Wars there were 920 industrial companies in Székelyudvarhely.
This number shouldn't mislead us, because we have to know that on average there were only two employes per company.
The number of the population decreased gradually: in 1910-10,244, in 1920-10,192, in 1930-8,158. In this period no public building was built.
But it is important to mention that the cultural life continued to flourish.
In 1921, the most important local paper the "Székely Közélet" wrote: "Cultural lectures, entertaining and moral reading, parties have been for months on end, as if we lived the most happiest times as if weren't economical crisis".

After the World War II came the socialist regime, a period of contradictions.
The population of the town increases, it is four times larger.
The villages become depopulated.
The people from the countryside are moved to town where they become proletarians but they can not adjust themselves to the requirements of a town life. Bethlenfalva and Kadicsfalva are annexed to Székelyudvarhely in 1952. The new housing estates (the Tábor and the Bethlen) solve the housing shortage for thousands of families but at the same time in the most patinate parts of the town are moved declassed, unassuming people. The large-scale industry was born.
But most of them haven't been able to face the conditions of the free competition of our decade.
But , we can say that it had a good side too.

Though it contributed to the depopulation of the villages it decreased the number of the Szeklers who wandered away to far away regions.

Undoubtedly the social, cultural and sport construction projects: the Arts Centre, the school buildings, the hospital, the stadium, the sports hall, have been very useful for the town.

All these represent our inheritance of several centuries which makes us hope that hardships of the transition period will pass, and Székelyudvarhely will become again a flourishing settlement, where the patina of the past and the economic prosperity will be in harmony.