The Siamese cat is one of the first recognized breeds of Asian cats.
I didn't know there was a breed of cat that's siamese
They are characterized by their blue almond-shaped eyes and triangular head shape.
Oh ok. So, It's not as if it's  literally a siamese cat with two cats conjoined? 
No. They are native to Thailand and became popular breeds in Europe and North America in the 19th Century.