Fact: While George Washington was our first president elected under the current Constitution, he was not the first president of the United States.
In 1781, the last of the thirteen original colonies ratified the Articles of Confederation. Not long after, the Congress unamimously elected John Hanson of Maryland as President with the title "President of the United States in Congress Assembled". Even George Washington himself referred to Hanson as "the president" at the time. Six more presidents were elected by Congress before the current Constitution was ratified making Washington actually the 8th president.

Fact: Although slavery was one of the major disagreements between the North and the South, those in the South were primarily fighting for their independence (most of them were too poor to own slaves anyway) and those in the North were fighting primarily to preserve the Union (most of them would never have risked their lives over the issue of slavery). Lincoln was very clear about this when he said "If I could save the Union without freeing any slave I would do it, and if I could save it by freeing all the slaves I would do it; and if I could save it by freeing some and leaving others alone I would also do that."