The French traveler Nicolay, who in 1551 accompanied Jews exiled from France to Constantinople, depicted the life, activities, trade and traffic, culture, and the social setting of the Jews in the following manner:
“Particularly astonishing is the immense number of resident Jews in Turkey and Greece, and particularly in Constantinople. Their number is continually on the rise, which is attributable to the fact that they almost everywhere are operating trade and goods and money, so that different kinds of products from all lands and peoples are brought either by land or sea and are promoted here. One can safely say that the traffic in trade and finance throughout the Levant currently, in great part, can be found in Jewish hands. In Constantinople, the biggest commercial zones with the most variety of goods in filled-up warehouses belong to Jews.
“Also with them one can encounter, and not seldom, artisans and skilled workers who were recently Marranos who fled from Spain and Portugal. They manufacture for the Turks the most varied of war armaments that have yet been discovered and developed, for example, cannons, arquebuses[Translator’s Note: an early, primitive musket], powder, munitions, etc. In the same manner, there are Jews here who have built publishing plants, which were heretofore unknown among the Turks, that print books in Latin, Greek, Italian, Spanish, and Hebrew. Related to this is the fact that Jews know many languages, so that many are happy to employ them as translators.”
Another Frenchman reported in a travel book that appeared in Paris in 1555 about Spanish Jews who worked in mines not far from Salonika alongside Jews from Hungary who arrived earlier, and who were called “aleman” [Germans]. He ascertained that the Jews built the main force behind all the commercial traffic, and that the Turkish government esteemed Jewish financial acumen.
The court physician Moses Hamon, whose father also had been a personal physician to the Turkish court, accompanied Sultan Suleiman II [Suleiman the Magnificent] on his military expeditions. Joseph of Naxos placed his entire worldwide connections at the disposal of Sultan Selim II, and worked for Turkey’s benefit. A relative of the duke of Naxos, and his successor in the diplomatic service to the Turkish court, was Don Salomo Abenjaex, who was also known as Chevalier Alvaro Mendez. Spain had exhausted Turkish neutrality against England, and Mendez thwarted their intentions by seizing Spanish warships in Italian waters and in the eastern Mediterranean Sea and rendered them harmless.
The discovery of America led to a shift of the trade with the Orient to the waters of the New World and caused a gradual decline in the Turkish economy (since previously it had all flowed to Europe through Constantinople). The Jews shared in the fate of this hospitable land.
In the 17th century Jews looking to escape [what had become a] hopeless reality were drawn to the false messiah Shabtai Zvi. The masses sank into superstition and ignorance.
In 1927 the current state of Turkey undertook a census for the first time, and in the European portion of Turkey counted about 55,000 Jews, about 4.7% of the total population. Mostly they lived in Istanbul – 46,700 – and in Edirne[formerly Adrianopolis] – 5,700. The reduction of the Jewish population can be seen from the 1908 estimate of the Jewish population. At that time, Constantinople [the name was changed to Istanbul at the end of WWI] had about 60,000 Jews and Edirne 25,000.
The masses of Jews busied themselves with shipping, piloting and captaining boats, freight hauling, small artisanship, and fishing. In the European quarter of Istanbul and in the suburb of Pera, the middle and upper classes predominated, occupying themselves as lawyers, doctors, and merchants.
The Peace Treaty of Lausanne in 1923 guaranteed Jews minority rights. The new Turkish republic promoted the assimilation of all into the state. Turkification of minorities was systematically carried out. Turkish became the official language of instruction in all the minority schools.
Due to the secular character of the new educational system, religious instruction was not allowed in public schools. Organized resistance by minorities was suppressed by the government and religious centers were closed. Jewish social relief organizations and Jewish schools found themselves in an unbearable financial position.
Of the 8,000 school-age-obligated [Jewish] children in Istanbul in 1929, 6,000 attended school, about 3,500 at Jewish schools, and 2,500 at Christian mission schools. Foreigners were not permitted to teach at the Jewish schools.
The new republic promised Freedom, Equality, and Brotherhood [the motto of the French Revolution] to all the citizens of the state, without distinction as to religion or ethnicity. However, the government demanded that minorities renounce the rights guaranteed to them by the Treaty of Lausanne, and the Jews complied. Family names were Turkified. Hebrew prayer books appeared with Roman letters. [When Turkey became a republic after WWI, the Arabic alphabet was dropped in favor of the Roman, or Latin, alphabet we use and which Turkey still uses to this day.]
After the separation of religion and state, the higher rabbinate, which had played such a large role in the history of Jews in Turkey, was stripped of its official character.
The Turkey of today  is no place for immigrants. The Law for the Promotion of Industry appears to mean that all enterprises, which may work to provide benefit to the state – which is to say, practically all enterprises, period – may employ only Turkish citizens. Foreigners who came to Turkey recently with the hope of finding opportunity were bitterly disappointed.
“The general economic situation,” reported an emigrant, “simply defies any description. We warn all Jewish immigrants thinking of going to Turkey…we are all totally and spiritually sick and broken-down. I think I’m losing my mind.”
On the other hand, a number of Jewish professors and high school managers from Germany were given employment at the reorganized University of Istanbul. A few engineers and merchants have managed to fill certain niches, but it’s only a handful.