Harold Joseph Traynor was born on November 11, 1898, in Framingham, Massachusetts to James and Lydia Traynor, Canadian immigrants. Harold was the second born out of seven children. When he was five, his family moved to Somerville, Massachusetts just outside of Boston. It was here where Traynor learned the game that would make him great. He would always beg the older boys in his neighborhood to let him play baseball with them, but was turned down because of his age. When he was finally allowed to play he was put behind the plate to retrieve foul balls. This is where he met Father John Nangle, a local clergyman, shopkeeper, and baseball fan.

This marks the beginning of the confusion surrounding Traynor's nickname. There are multiple stories about how he acquired the nickname "Pie." The first of three stories is that after baseball games, Father Nangle would have the team over to his corner store for snack and Traynor would always ask for a slice of pie. It is said that Father Nangle began calling him "pie face" and was later shortened to "pie." The second story surrounding his nickname is that he gained it because of his fondness for his mother's pies. Lastly, one day upon returning home from a day of playing outside he was very dirty and his father, a printer, said you look like "pied type."

Life was not all baseball for young Traynor; he began work at age twelve as a messenger boy and office hand to help supplement his family's income. Traynor played pick-up baseball growing up and then played for his high school team in Somerville. In 1917, U.S. involvement in World War I began and Traynor tried to enlist in the army, but was turned down. Even though he was turned down, he still wanted to serve so he moved to Nitro, West Virginia and became a "car checker" for the railroad, checking cars filled with explosives. Shortly after taking the job, he returned home to work at an Army Base pier in Boston.

After the war, Traynor had a tryout with the Boston Braves. However, the scout who had invited Traynor never told the manager and upon seeing Traynor, the manager sent him home. At home, he played for Falmouth in the Cape League instead. Then in 1920, Traynor signed a $200 dollar a month contract with Portsmouth of the Virginia league. In his first season, he batted .207 in 104 games and major league clubs took notice. On September 11, 1920, the Pittsburgh Pirates bought Traynor's contract from Portsmouth for $10,000--the most ever paid for a Virginia league player. Traynor had a rough first year batting .212 and had 12 errors in 17 games and was sent down to the Birmingham Barons, with whom he spent most of the 1921 season. In that season he hit .336 and stole 47 bases but had 64 errors at shortstop. Nonetheless, the Pirates called him back up later in the year. After starting three consecutive games for the Pirates, he made an error, which cost them the game. He was benched and only played in two more games that year.

In 1922, the Pirates made a change hiring Bill McKechnie as the new manager and he moved Traynor to third base, his natural position. In his rookie year, Traynor batted .282, but the following season he batted .338. This began his streak where he hit better than .317 for seven out of eight years. From 1927 to 1930, he did not bat below .337. He hit over 300 for ten out of the 17 years of his career and had a lifetime batting average of .320. Despite these great statistics, Traynor only led the Pirates in hitting once, because he played on a team with the Waner brothers, themselves inductees of the Baseball Hall of Fame. Furthermore, Traynor was a great contact hitter and only struck out 278 times in his career. He won two pennants with the Pirates and in 1925, they beat the Washington Senators in the World Series. During the World Series he hit .346. In 1927, the Pirates played the Yankees in the World Series. The Murderers Row Yankees swept the Pirates and Traynor could only hit .200.

In the summer of 1930, Traynor got engaged to a 25-year-old telephone operator named Eve Helmer. Helmer worked at the Havlin Hotel in Cincinnati, where the Pirates would stay during road trips. Traynor met her because the switchboard for the telephone was in the lobby of the hotel. Traynor, who was shy around girls, immediately had a connection with Eve because she was a baseball fan. Traynor married Eve on January 3, 1931. They went on their honeymoon to California and then moved to Paso Robles for spring training.

Later in his career, he developed into an excellent fielder, he had great range at third base and could challenge bunts. Traynor's fielding was also helped because he was paired with defensive great Glenn Wright, who played shortstop. In 1934, he became the player/manager of the Pirates, taking over for George Gibson. During that season, he broke his arm sliding into home and that injury shortened his career. Traynor ended up retiring in 1937 and was replaced as manager in 1939, holding the record for the second most wins in Pirates history.

After his retirement, Traynor became a scout for the Pirates and then a radio broadcaster for 20 years. He also announced professional wrestling. In 1945 Traynor began hosting a radio program six days a week on KQV called The Pie Traynor Club where he talked baseball with local kids. People loved listening to Traynor do his broadcasts but he was not smooth and he did not use a script. In 1948, Traynor was elected to the Pro Baseball Hall of Fame. Then the early 1950's he helped to found the Pittsburgh Professional Baseball Association, an association formed to raise money for a statue of Honus Wagner. Traynor lost his job with KQV in 1966, because The American Broadcast Company, which owned KQV, preferred Howard Cosell to Traynor. Then in 1969, Traynor was selected as a member of the All-Time Team for baseball's centennial. Traynor continued to work with the Pirates organization throughout his life. Later, he contracted emphysema and his health began to deteriorate. Traynor died March 6, 1972. He is buried in Homewood Cemetery in Pittsburgh, Pennsylvania.