Little League World Series was created in 1947.
Little League World Series Baseball was created in 2008.
By Junior Division I assume you mean what Little League calls the Junior League. I am afraid I cannot find that information. Little League's website, littleleague.org, has complete data for Central Region and Junior League World Series participants back through only the 2002 season. This year's team from Glendale is the only team I have found that has made the World Series. Teams from Wisconsin in the Central Region playoffs from 2002-2007 have come from Oak Creek, Franklin Little League, Whitefish Bay, Madison, and the last two years from Glendale. They list an email address of webmaster at littleleague.org to direct questions and comments. You might try contacting them to see if they have any information. The city of Taylor, Michigan, where the Junior League World Series is held, also has a website that has a section devoted to the World Series. Unfortunately, other than a list of past champions, there is no historical data to be found. They do list an email address to reach the World Series Director Greg Bzura (gregb at wwwnet.net) and Director of Public Information for both the City of Taylor and the World Series David Gorgon (taylornews at aol.com).
World Rowing Junior Championships was created in 1967.
Hockey Junior World Cup was created in 1979.
World Junior Chess Championship was created in 1951.
Women's Hockey Junior World Cup was created in 1989.
FINA World Junior Swimming Championships was created in 2006.
Individual Speedway Junior World Championship was created in 1977.
IAAF World Junior Championships in Athletics was created in 1986.
Men's Junior Volleyball World Championship was created in 1977.
Team Speedway Junior World Championship was created in 2005.