 He graduated from the University of Bonn in 1851 with a doctorate in linguistics, after a period in Berlin where he went to study Hebrew and where he first became interested in African languages.Bleek's thesis featured an attempt to link North African and Khoikhoi (or what were then called Hottentot) languages – the thinking at the time being that all African languages were connected.After graduating in Bonn, Bleek returned to Berlin and worked with a zoologist, Dr Wilhelm K H Peters, editing vocabularies of East African languages.