The surname Blackmun was first found in Durham but also in other areas of Britain including John Blakeman who was listed in Devon during the reign of Henry III  and in Norfolk where Blacheman filius Aedwardi was listed in the Pipe Rolls of 1166. Jordanus filius Blakeman was listed in the Pipe Rolls of Hampshire of 1188. A few years later the Pipe Rolls of 1206 listed John Blakeman in Surrey. 
Early History of the Blackmun family
This web page shows only a small excerpt of our Blackmun research. Another 123 words (9 lines of text) covering the years 108 and 1086 are included under the topic Early Blackmun History in all our PDF Extended History products and printed products wherever possible.
Blackmun Spelling Variations
Although the name, Blackmun, appeared in many references, from time to time, the surname was shown with the spellings Blackman, Blachman, Blackmann and others.
Early Notables of the Blackmun family (pre 1700)
More information is included under the topic Early Blackmun Notables in all our PDF Extended History products and printed products wherever possible.
Migration of the Blackmun family
Gradually becoming disenchanted with life in Ireland many of these uprooted families sailed aboard the armada of sailing ships known as the "White Sails" which plied the stormy Atlantic. These overcrowded ships often arrived with only 60 to 70% of their original passenger list, many dying of cholera, typhoid, dysentery or small pox. In North America, some of the first immigrants who could be considered kinsmen of the Blackmun family name Blackmun, or who bore a variation of the surname were John Blackman who settled in Dorchester in 1640; Nicholas Blackman who settled in Virginia in 1624; Thomas Blackman settled in Barbados with his wife, children and servants in 1679..
Harry Andrew Blackmun (1908-1999), American jurist, Associate Justice of the Supreme Court of the United States (1970-1994), Judge of the United States Court of Appeals for the Eighth Circuit (1959-1970)
Martin G. Blackmun, American politician, U.S. Vice Consul in Melbourne, 1945-46