What empire did the songhay empire replace?

on this day in 1913, henry ford installs the first moving assembly line for the mass production of an entire automobile. his innovation reduced the time it took to build a car from more than 12 hours to two hours and 30 minutes.

the monroe doctrine is the best known u.s. policy toward the western hemisphere. buried in a routine annual message delivered to congress by president james monroe in december 1823, the doctrine warns european nations that the united states would not tolerate further colonization or puppet monarchs.