As we look forward to another season of baseball, it's a good time to also look back at some giants of the game who played before Jackie Robinson broke the color barrier in 1947.

For decades, the Negro Leagues featured some of the greatest baseball players in America. And while discrimination kept them out of the major leagues, fans flocked to games and the sport was played at a highly professional level.

Legendary stars of the Negro Leagues included pitcher Andrew "Rube" Foster, who taught the screwball to pitching legend Christy Mathewson; Frank Grant, an infielder considered the best black baseball player of the 19th century; Willard "Home Run" Brown, who led the mighty Kansas City Monarchs in the 1930s and 1940s; James "Cool Papa" Bell, who may have been the fastest man to play the game; and the mighty Josh Gibson, who is remembered as "the black Babe Ruth."

The great Jackie Robinson played for the Kansas City Monarchs before breaking in with the Dodgers. And other players also began in the Negro Leagues and moved to the majors, including Larry Doby, the first black player in the American League, and Satchel Paige, the great pitcher whose best years were spent hurling for the Kansas City Monarchs.

In a sense, it's sad that the Negro Leagues even existed. Yet, we should always honor the achievements of the men who played some of the greatest baseball ever.

Photograph: Statue of James "Cool Papa" Bell outside Busch Stadium in St. Louis/Getty Images

In the 1840s newspapers began using a term Underground Railroad to refer to a mysterious network by which escaped slaves would travel northward, eventually finding freedom in Canada.

To some Americans, assisting escaped slaves was noble work. Yet it was also a serious violation of the federal laws pertaining to fugitive slaves, meaning such activity had to be kept very quiet.

A secretive organization by necessity, the Underground Railroad kept no records, and much of what we know about it is based on accounts written years later. But what is known is quite remarkable.

Men such as Levi Coffin organized groups of Quakers in Ohio and Indiana who helped transport slaves who had crossed the Ohio River from Kentucky.

And the heroic Harriet Tubman, who escaped from a life of slavery in Maryland, made many trips back into slave territory to lead others to freedom. She was called "Moses" by many, and the fanatical abolitionist John Brown called her "General Tubman."

While many of the workings of the Underground Railroad may always remain a secret, we do know that it did exist, and it did help thousands of slaves find new lives in freedom.

Photograph: Harriet Tubman/Library of Congress

Born into slavery in New York State in the 1790s, Sojourner Truth never learned to read or write. Yet she became known as a passionate and intelligent advocate for the abolitionist cause as well as for women's rights.

As she did not write down her speeches, we have to rely on accounts of those who heard her speak, and some of the accounts are disputed.

What is clear is that she was involved in religious and utopian movements in New York before moving on to becoming very involved in the abolition movement. She became known as a feminist and anti-slavery speaker.

Sojourner Truth, lacing her speeches with recollections of her life as a slave, radiated moral authority. And her concerns, which she expressed before many audiences, would provide inspiration for the feminist movement as well as the Civil Rights Movement of the 20th century.

More about Sojourner Truth:

• Biography of Sojourner Truth
• Transcript of her Ain't I A Woman? speech
• Vintage Images: Sojourner Truth

Photograph: Sojourner Truth/Getty Images

As we commemorate Black History Month, it's an ideal time to pay tribute to the life and career of historian Carter G. Woodson, who is often cited as the creator of the field of African-American History. Woodson, who passed away in 1950, did not live to see the great achievements of the Civil Rights Movement, but his groundbreaking work inspired many and led to the creation of Black History Month.

Woodson promoted the week of February 7, 1926 as the first Negro History Week, as it would include the birthdays of Abraham Lincoln and Frederick Douglass. Woodson's hope was that young African Americans would celebrate the accomplishments of their ancestors.

Over the years the tradition developed of observing Negro History Week. And during America's bicentennial celebrations in 1976 the idea was expanded to Black History Month, which was made official by President Jimmy Carter in 1978.

Illustration: Historian Carter G. Woodson/Getty Images