When family surnames were first required in Turkey and Iran?

Question:how did the families decide what surname to use?

Best Answer - Chosen by Asker: how did the families decide what surname to use?

1930's for Turkey http://www.turkeytravelplanner.com/phpBB...
However, before that, they used "nicknames" in much the same was as surnames; they were also known by their clan names.

http://www.turkishodyssey.com/turkey/his...
wow.. according to this, surnames were not required until 1934!
Some of the other history might help you... background is often helpful to understand what our ancestors did.