Short answers, pulled from the story.
Hägar the Horrible first appeared on the 4th of February 1973 in Sunday papers, and the following day in daily newspapers. It was an immediate success and was created by cartoonist Dik Browne, syndicated by King Features Syndicate.
Hägar the Horrible is distributed to 1,900 newspapers in 56 countries and is translated into 12 languages.
Hägar the Horrible was created by cartoonist Dik Browne. The name originated as a nickname his sons gave him, Hagar the Terrible, which Browne adapted for the strip using Hägar the Horrible for alliteration. According to his son Chris, the name is pronounced Hay-gar.
Dik Browne retired in 1988 and his son Chris Browne continued the strip until his 2017 retirement, with artwork by Gary Hallgren. Currently the strip is produced by staff members of Browne Creative Enterprises, run by Bob Browne and his sister Tsuiwen Browne-Boeras, the two surviving children of Dik Browne.
Yes. On the 1st of November 1989, Hanna-Barbera produced Hägar the Horrible: Hägar Knows Best, which aired on CBS. The special starred Peter Cullen as Hägar, Lainie Kazan as Helga, and was based on the strip's first plotline from 1973.
Dik Browne co-created the comic strip Hi and Lois with Mort Walker, who also created Beetle Bailey. Browne was reportedly the real-life inspiration for Plato, the intellectual private in Beetle Bailey.