Earliest immigrants to north america were required to adapt to which initial environmental challenge

The earliest immigrants to North America were required to adapt to the glaciers and ice.

These immigrants arrived during the period of Wisconsin glaciation when the ice and glacier caused the sea level to drop and hence the immigrants adapted to life in the icy climate. The drop in the sea level caused an exposure of a land bridge that connected Siberia and Alaska.

the emancipation proclamation was the aim of the war change to include the freeing of slaves in addition to preserving the union. the 13th amendment, which abolished slavery in the u.s. was passed on december 6th 1865.

as promised, lincoln waited to unveil the proclamation until he could do so with success from the union military advance. on september 22nd 1862, after a victory at antietam, he publicly announced a preliminary emancipation proclamation, declaring all slaves free in the rebellious states as of january 1st 1863.