Iasi was first mentioned in a commercial document issued in 1408 by the Moldavian ruler Alexandru cel Bun. However, because there were older buildings that date (eg. The alleged Armenian Church build in 1395), it is believed that the city is much older than 1408, at least a few decades.
In 1564, the ruler Alexandru Lapusneanu moved the Moldavian capital from Suceava to Iasi. In 1640, Vasile Lupu established the first school here in Romanian and a typography in the Three Hierarchs Church. In 1643, the first printed book in Moldova appeared in Iasi.

The city was burned down by the Tatars in 1513, by the Ottomans in 1538, and the Russians in 1686. In 1734, was affected by an epidemic plague. Through the Peace treaty signed in Iaşi, the sixth Russian-Turkish War ended in 1792. In 1822, the Turks stormed the city to quell the Greek revolutionaries of Eteria, led by Alexandru Ipsilanti.
Between 1565 and 1859, the city was the capital of Moldavia, then, between 1859 and 1862, both Iaşi and Bucharest were de facto capitals of the United Principalities of Moldavia and Wallachia. In 1862, when the union of the two principalities was recognized under the name of Romania, the capital was established in Bucharest. To compensate the losses caused by changing the seat of government, was voted to pay 148 150 lei to city, but this never happened.
After 1860, wood and mud buildings were gradually replaced with ones of stone and brick, and the street network has been improved. New establishments were built as the Palace of Culture, the National Theatre and the University “Alexandru Ioan Cuza”.
During the First World War for two years, Iasi was the capital of the free Romania, after Bucharest fell to the Central Powers on 6 December 1916. In November 1918, the capital was moved to Bucharest.
World War II was a dark period in the history of Iasi. During the Antonescu regime, Iasi pogrom of June 27 to 29, 1941 was one of the worst events of its kind in the world, too little known by the inhabitants of Iasi themselves, both before and after the Romanian Revolution of 1989. In May 1944, the city was the scene of heavy fighting between Romanian-German forces and the Red Army, days in which much of the historical areas of the city was destroyed.
Famous elite Panzergrenadier Division “Grossdeutschland” won an important victory over the Soviets in the Battle of Targu Frumos, near Iasi. In July, Iasi was occupied by Stalinist forces.
In the postwar period, the city continued to grow, building new neighborhoods and industrial enterprises. After the fall of communism, the city remained the most important cultural center outside the Carpathian arch, after Bucharest. Iasi could obtain the title of “city initiator of the Revolution of 1989” by government ordinance, in 14 December 1989, many citizens were being arrested for had organized a rally against the communist regime. Uprising signal should be given by the bells of the Metropolitan Church. The revolutionary plan was however found by Security. At the time fixed, Union Square was strictly supervised by militiamen, which prevented any demonstration, and the Popular Front members were arrested. they were released a few days later, in December 22, 1989.