Born and raised in Steubenville, Ohio, he played in the Federal League in 1914 for the Indianapolis Hoosiers, moving with them to New Jersey in 1915 where they became the Newark Peppers.

Kaiserling won 17 games for pennant-winning Indianapolis in 1914 and finished seventh in the Federal League with a 2.24 earned run average (ERA) in 1914.

Little is known of Kaiserling's early life, but the 1910 United States census reports that he still lived with his family in Steubenville and had not married.

[3] Kaiserling began playing baseball professionally in 1910 with the Great Bend Millers of the Class D Kansas State League.

[3] In 1911, Kaiserling pitched for two Class D teams in Illinois, splitting the season between the Lincoln Abes and the Clinton Champs of the Illinois–Missouri League.

Daunted at spring training because 12 pitchers were competing for roster spots, he asked to be released so the Champaign Velvets of the Illinois–Missouri League could sign him.

[5] By August, fans and reporters considered him a league star, bestowing him with the nickname, "Der Kaiser" (or "The Emperor", in English).

[3] Before the 1913 season, the Indianapolis Indians of the Class AA American Association purchased Kaiserling's contract, hoping the pitcher could help them improve off of a last-place finish in 1912.

Frustrated by Kaiserling's lack of focus on conditioning and learning how to pitch, the Indians sold his contract to the San Francisco Seals of the Class AA Pacific Coast League on July 26.

Indianapolis had the league's best record at the time they acquired Kaiserling, and manager Bill Phillips hoped the pitcher could help them in the pennant race.

Kaiserling had another shutout going through six innings but gave up three hits and a run in the seventh; however, Indianapolis still clinched the series with a 4–1 victory.

[1] His start against the Kansas City Packers on April 20 is considered his major league debut; Kaiserling earned the victory in a 7–2 triumph.

[1] Used only seven times in the early part of the season, he had a 1–1 record through June 10, as the Hoosiers were in only seventh place in the eight-team league.

[7] The last game of the stretch, against St. Louis, was what baseball historian Frank Russo called "his personal highlight of the season"; Kaiserling limited the Terriers to one hit in a 3–0 victory.

This prompted The Washington Times, in reference to the ongoing war in Europe, to quip, "When looking for gunners how did Wilhelm of Germany miss Kaiserling of the Hoosiers, who hit 17 batters last season?

[13] His record hovered around .500 all year, but on October 3, in his last start of the season, he gave up seven runs (six earned) to the Baltimore Terrapins, falling to 14–15 with the loss.

[13] Newark finished the season with 80 wins, 72 losses, and 3 ties, only good enough for fifth place in the league but a mere six games behind the pennant-winning Chicago Whales.

[1][16] Kaiserling's 3.0 WAR was tenth among Federal League pitchers, his five shutouts were tied with seven others for fourth, and his 0.034 home runs per nine innings pitched was decimal points behind Eddie Plank's similar total.

Various reports tied Kaiserling to the Indianapolis Indians and the Detroit Tigers, but it was the Toledo Iron Men of the American Association who signed him on March 7, 1916.