July 21st, 1861:

(AP Photos)

(SOT of "When Johnny Comes Marching Home")

During the American Civil War, Union and Confederate forces fight the first Battle of Bull Run in Manassas, Virginia.

The war's first major battle ends in a Confederate victory. So does a second battle at Bull Run the following year.

1925:

(AP Photos)

In Dayton, Tennessee --- the end of what's known as the "Scopes Monkey Trial."

John Scopes is convicted of violating state law for teaching Darwin's theory of evolution in science class.

That conviction is later overturned on a technicality.

1954:

(AP Photos / AP Archive Video)

A peace deal concludes nearly eight years of fighting in what's then known as French Indochina, in Southeast Asia.

The deal splits Vietnam into a communist North and non-communist South, as France ends its colonial rule in the region.

Over the next decade, American involvement in Southeast Asia grows, culminating in the Vietnam War.

1899:

(AP Photos)

Author Ernest Hemingway is born in Oak Park, Illinois.

Among his works: The Sun Also Rises, A Farewell To Arms, For Whom The Bell Tolls, and The Old Man And The Sea.

And, 1951:

(AP Photos)

(SOT of Williams)

Robin Williams --- the actor and comedian known for his impersonations and movie roles --- is born in Chicago.

Today in History, July 21st --- Sandy Kozel, The Associated Press.