|Probably married to Dorothea Mumme (born 1819 died after 1880 and before 1900)|
It is not clear if he died in Germany or in the USA. But according to David Carl Mumme, he died in Germany.
Fact is, he did not travel with his family. If he travelled ahead to buy and build up a farm, then the farm would be under his name when the rest of the family arrived in 1873.
Then after his death Dorothea would be the head of the family. But in 1880, William was the head of the family and his mother Dorothea lived with him.
Also according to David Carl he had another son Henry/Heinrich, who came first to the USA.
Heinrich is probably identical to Johann Karl Heinrich Mumme