https://www.cell.com/ajhg/fulltext/S0002-9297(12)00271-6
"The estimated time (3 kya) and the geographic origin (the Levant) of the gene flow into Ethiopia are consistent with both the model of Early Bronze Age origins of Semitic languages and the reported age estimate (2.8 kya) of the Ethio-Semitic language group. They are also consistent with the legend of Makeda, the Queen of Sheba."