Short answers, pulled from the story.
Guin Saga has 150 main volumes and 27 side-story novels. The series began publication in 1979, and the last twenty main volumes and six side stories were published posthumously after author Kaoru Kurimoto died in 2009.
Kaoru Kurimoto was the Japanese author who created Guin Saga. She died in May 2009, three days after becoming too ill to continue writing what would have been volume 130 of the series, on the 23rd of May 2009.
Guin Saga is recognized as the longest single-writer's work in the world, with total sales of 30 million copies. Kaoru Kurimoto wrote continuously from 1979 until her death in 2009, producing 130 volumes herself before the series was continued by other authors.
Nobuo Uematsu, known for his video game compositions, composed the score for the Guin Saga anime. It was his first full soundtrack for an anime. The two-CD soundtrack was released on the 24th of June 2009.
American publisher Vertical released the first five volumes of Guin Saga in English, translated by Alexander O. Smith. The English editions drew comparisons to The Lord of the Rings and Conan the Barbarian.
Yū Godai published Volume 131, Parro no Ankoku, on the 8th of November 2013, resuming the main story four years after Kurimoto's death. Yume Yoshino followed with Volume 132, Cylon no Banka, in December 2013.