We know that Abraham, the first father of the Jewish people, came from Ur Kasdim (Ur of the Chaldees) in Sumer. We also know that
modern historians have asserted that Sumer was first settled between ca. 4500 and 4000 BC by a non-Semitic people who possibly did not speak the Sumerian language (pointing to the names of cities, rivers, basic occupations, etc. as evidence). These conjectured, prehistoric people are now called "proto-Euphrateans" or " Ubaidians", and are theorized to have evolved from the Samarra culture of northern Mesopotamia. The Ubaidians were the first civilizing force in Sumer, draining the marshes for agriculture, developing trade, and establishing industries, including weaving, leatherwork, metalwork, masonry, and pottery. However, some, such as Piotr Michalowski and Gerd Steiner, contest the idea of a Proto-Euphratean language or one substrate language. Sumerian civilization took form in the Uruk period (4th millennium BC), continuing into the Jemdat Nasr and Early Dynastic periods.It was conquered by the Semitic-speaking kings of the Akkadian Empire around 2270 BC (short chronology). Native Sumerian rule re-emerged for about a century in the third dynasty of Ur (Sumerian Renaissance) of the 21st to 20th centuries BC[2100 BC to 1901 BC].
So two ancient peoples inhabited Ur Kasdim, one non-Semitic and one Semitic. To which group did Abraham belong? It is tempting to think Abraham may have been Akkadian, given that many months in the Hebrew calender have ancient Akkadian names and we know Abraham was a descendent of Shem. Additionally, tradition places Abraham's birth sometime around the early 2nd millennium BC, into which the 20th century BC falls - at the time when Native Sumerian rule re-emerged and Akkadian rule declined. This could have propelled Abraham,potentially of Semitic Akkadian origin, to leave Ur Kasdim. But, all this is not proof of Abraham's Akkadian genetics, and only hints to the culture he had acquired and preferred while living in Ur Kasdim. Perhaps Abraham merely liked the Akkadian culture (which had been there for a long while before Abraham's time, and was the culture within which he may have grown up), while he didn't so much like the culture of the Native Sumerians (which may have reemerged to power during Abraham's time).
More importantly, tradition also disputes that UR Kasdim was Abraham's birthplace, instead suggesting (with Ramban supporting) that Haran (alternatively spelled Charan) was Abraham's native land and birthplace. Even if Abraham himself was born in Ur Kasdim (hosting both Semitic and non-Semitic populations), Abraham's father Terah was born in Haran (the House of Terah was in Haran), making Haran Abraham's genetic homeland. Haran is not Semitic Akkad. Biblical Haran is a Semitic Assyrian city whose ruins are in present-day Turkey. This indeed is a very interesting idea, as "all the children of Jacob (called Israel) are descended from Haran, through his daughter Milcah (and through Abraham's father Terah)," and as many Ashkenazi Jews genetically hail from the regions of Turkey (and are told they are likely descendents of the ancient Khazars and not of "original Semitic Jewish bloodlines").
So, was Abraham Semitic? I think both the genetic evidence and Torah tradition tell us that Abraham was most likely genetically from the area of Turkey (ancient Anatolia). So, yes, I suppose he was, as Turkey and Assyria are of Middle/Near Eastern location, and Turkey/Assyria seems to have been a place where Shem's descendents (at least Terah and his clan) settled.