Valenti Angelo was born on June 23, 1897, in Massarosa, Tuscany, Italy. During his early childhood, the village woodcarver encouraged him to become an artist. At the age of eight, Angelo immigrated with his family to the United States, where he attended schools for a brief time in California. At fifteen, he joined the labor force, working first in a paper mill and then in rubber, glass, and steel plants. In 1916 he moved from his parents' home to San Francisco in order to continue his artistic education. He married Maxine Grimm in 1923 and had two children.
Angelo's first break came during the three years he worked for a photo engraving company. He began illustrating books for Grabhom Press in 1926, and his skillful illustrations and decorative pieces were recognized as accomplished works of art. In 1933 Angelo became a free-lance artist, gaining an even greater reputation in the field of graphic arts. Thirty-seven books containing his illustrations have been included in the American Institute of Graphic Arts' Fifty Books of the Year Exhibitions. In 1937 he began to write the children's books that he illustrated.
During his active years as a writer, from before World War II to the 1960s, Angelo earned praise as an exceptional storyteller. Writing of the places and times with which he was most familiar, he often describes the world through the eyes of an immigrant youth. His books frequently express his affection for both America and Italy, yet his universal insights into the hearts and minds of the young defy ethnic and cultural barriers.