Ankara Treaty of Lausanne (1923), the Turkish nationalists replaced the Ottoman Empire with the Republic of Turkey on 29 October 1923. A few days earlier, Ankara had officially replaced Constantinople as the new Turkish capital city, on 13 October 1923. After Ankara became the capital of the newly founded Republic of Turkey, new development divided the city into an old section, called "Ulus", and a new section, called "Yenişehir". Ancient buildings reflecting Roman, Byzantine, and Ottoman history and narrow winding streets mark the old section. The new section, now centered on Kızılay Square, has the trappings of a more modern city:
History of Ankara end of the 4th century, St. Jerome, a native of Galatia, observed that the language spoken around Ankara was very similar to that being spoken in the northwest of the Roman world near Trier. This may indicate that the older Phyrigian population had adopted the language of the Celtic invaders. The city was subsequently conquered by Augustus in 25 BC and passed under the control of the Roman Empire. Now the capital city of the Roman province of Galatia, Ancyra continued to be a center of great commercial importance. Ankara is also famous for the "Monumentum Ancyranum" ("Temple of Augustus