Polygamy among Native Americans

Polygamy was recognized by the Sioux of the great plains, and is described by Francis Parkman in The Oregon Trail.

Polygamy was also practiced in Baja California.  The missionary Father Nicolas Tamaral wrote in the mid 1700s: "We proceeded very slowly with these poor savages... because of their remarkable dullness to learn and to make themselves capable of grasping the sublime mysteries of our holy faith.  This is owing to the awful vices in which, as pagan savages, they are steeped, to the superstitions to which they are attached, to the wars and murders prevalent among them, but especially to the mire of impurity into which they are plunged.  It is extremely difficult to persuade them to resolve to dismiss the great number of wives that each one has; for the poorest and lowest have two or three and more wives because among these Indians the feminine sex is more numerous."

"This obstacle is the most difficult to overcome, partly because the women that are put away by one man do not easily find another who will take them.  Another reason is that the men, if reduced to one wife according to our holy law, would find themselves compelled to go in search of food; but having been raised in absolute idleness, they will lie in the shade of a tree, whither the women insist upon bringing an abundance of seeds and wild fruit, each trying to fetch more than the other wives.  Hence, to induce men so lazy and indifferent, and raised in such a beastly manner, to lead a rational life, to put away the women and to be content with one wife, to take the trouble of procuring food for themselves and their children, to submit to everything that is disagreeable to a savage people, and to resolve to embrace the Christian life, requires a miracle of Divine grace."

Source for quotes on polygamy in Baja: The Forgotten Peninsula: A Naturalist in Baja California, by J.W. Krutch, p. 110-11. While Krutch thinks "the padres meant well," he shares their contempt for the original Lower Californians.  More on Baja missionaries.