How did the Crusades directly cause the Renaissance?

They opened the door for the travelers to visit East, but also spread the learning on Ancient Greek civilization to the west.

Explanation:

Although Crusades were mostly connected with the religious wars from the 11th until 13th Century, they established certain connections between East and West and caused the revival of interest for the knowledge of ancient period. Many scholars were re-discovered, and that is why Crusades had a good effect when looking through that perspective.

abraham lincoln  (february 12, 1809  – april 15, 1865) was an american statesman, politician, and lawyer who served as the 16th  president of the united states  from 1861 until  his assassination  in april 1865. lincoln led the nation through the  american civil war, its bloodiest war and its greatest moral, constitutional, and political crisis.[2][3]  he preserved the  union,  abolished slavery, strengthened the  federal government, and modernized  the u.s. economy.