We came across this great article on HearaldOnline.com about the history of lighting baseball games.

EAST CLEVELAND, Ohio — The magical experience of baseball played under the lights may have been most aptly described by James T. Golden, Jr., a Cincinnati Enquirer sports writer. He wrote of the first Major League Baseball game played under lights in 1935, “…The sphere stood out against the sky like a pearl against dark velvet.” Night baseball is a special experience for fans—it’s literally a more electric atmosphere.

Origins of the Night Game
Just like a player’s trajectory, night baseball started in the minors. R.J. Swackhammer, a GE lighting designer, created the lighting layout for the first Minor League Baseball night game in 1930. Major League Baseball night games trace their roots to a struggling early 1930s Cincinnati Reds team, with average weekday game attendance floating between 2,000 and 3,000 fans. People were working during prime daylight hours and catching a baseball game rather than working was an oft-unaffordable splurge.

Leland “Larry” MacPhail and Powel Crosley, the then-respective general manager and owner of the Reds, noticed a positive correlation between lights and attendance in Minor League Baseball parks. Despite the team’s financial woes, the Reds boldly decided to install lights at Crosley Field. They may not have known it at the time, but they sparked a lighting revolution in Major League Baseball.

On May 24, 1935, the first night baseball game was played under GE lights with more than 20,000 fans in attendance—about 10 times the number that had been attending day games. For the seven games played under the lights at Crosley Field that first year, average attendance stood at 18,500 fans. It was a success that forever changed how baseball would be played and experienced.

Red Barber, who announced the first Major League Baseball night game, observed, “As soon as I saw the lights come on, I knew they were there to stay.”

By 1941, just six years after the first Major League Baseball game was played under the lights, 11 of the 16 Major League Baseball fields had lights installed. During the 2012 regular season, the National League played 66 percent of its games at night, while the American League played 68 percent of its games at night.

Read more here: http://www.heraldonline.com/2012/10/25/4365733/shining-a-light-on-night-baseballs.html