Can anyone tell me if Baklava is a Turkish pastry or a Greek pastry

I believe it´s a Turkish one. But many people outside Turkia believe it´s a Greek one.

Wikipedia also states it:

The history of baklava is not well documented. It has been claimed by many ethnic groups, but there is strong evidence that its current form was developed in the imperial kitchens of the Topkapı Palace based on a Central Asian Turkic tradition of layered breads.

Is there truth to what Ive heard about Baklava really originally being from Gaziantep, which also is known for lahmacun and copper goods? I may have read that it was on the Silk Road trade rout, and that was when Turkey was introduced to many other foods from Syria?(künefe, köfte, kebabs, etc) 

Gaziantep has the best baklava, because pistachio nuts come from that region. The nuts are a main ingredient in baklava. Wether or not it is originally from there cannot be stated. And if one person could answer the question if it is Greek or Turkish, world peace will be amongst us And which came first...raki or ouzo. Cazik or Tzaziki... Turkish or Greek? Etc. etc. etc. The truth is that Greece in its current form and Turkey in its recent form are very recent. You can´t trace these things back so easily to the countries with their current borders.

In the end, it doesn´t really matter.  It´s just good stuff!