Mitt Romney's Polygamous Ancestors

Of Mitt Romney's 4 great-grand-fathers, 2 were polygamous: Miles Park Romney (who had 5 wives and 31 children and moved to Mexico in 1885)  and Helaman Pratt (who had 3 wives and 20 children and moved to Mexico in 1876). 

Of Mitt Romney's 8 great-great-grand fathers, 4 were polygamous: Archibald Newell Hill (who had 5 wives and 14 children);  Parley Parker Pratt, Sr. (who had 12 wives and 30 children and was murdered by the jealous husband of his 12th wife); Carl Heinrich "Charles Henry" Wilcken (who had 4 wives and 21 children and deserted from the US Army in 1857); and Lewis Robinson (who had 4 wives and 23 children).

In addition, his great-great-grandmother Elnora Warner Berry Dalton, (mother of Mitt's great-grandmother Rosetta Berry, whose father was Robert Berry), took as her 2nd husband Simon Dalton (who had 5 wives and an unknown number of children).  She had two surviving children from her first marriage, and six from her second.  In fairness to her, she believed that her first husband had abandoned her, but she never divorced him.

Also, great-great-grandfather Miles Romney (father of Miles Park Romney) was sealed to 11 women by proxy in 1872, but these could not be considered marriages.

See:  A Brief Guide to Mitt Romney's Polygamous Heritage.
Mitt Romney's Ancestry