Almost everything in his short life is recorded somewhere, being himself a regular diarist and prolific letter writer, much of the material having survived.
His biographers, however, have faced difficulty in translating his writings because of Rizal's habit of switching from one language to another.
Following custom, he delivered an address in German in April 1887 before the Anthropological Society on the orthography and structure of the Tagalog language.
He left Heidelberg a poem, "A las flores del Heidelberg", which was both an evocation and a prayer for the welfare of his native land and the unification of common values between East and West.
Like many families in the Philippines, the Rizals were of mixed origin.
José's patrilineal lineage could be traced back to Fujian in China through his father's ancestor Lam-Co, a Chinese merchant who immigrated to the Philippines in the late 17th century.He painted, sketched, and made sculptures and woodcarving.He was a prolific poet, essayist, and novelist whose most famous works were his two novels, Noli Me Tángere and its sequel, El filibusterismo.He is widely considered one of the greatest heroes of the Philippines and has been recommended to be so honored by an officially empaneled National Heroes Committee.However, no law, executive order or proclamation has been enacted or issued officially proclaiming any Filipino historical figure as a national hero.From Heidelberg, Rizal wrote his parents: "I spend half of the day in the study of German and the other half, in the diseases of the eye.Twice a week, I go to the bierbrauerie, or beerhall, to speak German with my student friends." He lived in a Karlstraße boarding house then moved to Ludwigsplatz.In 1697, to escape the bitter anti-Chinese prejudice that existed in the Philippines, he converted to Catholicism, changed his name to Domingo Mercado and married the daughter of Chinese friend Augustin Chin-co.On his mother's side, Rizal's ancestry included Chinese, Japanese and Tagalog blood.He was executed by the Spanish colonial government for the crime of rebellion after the Philippine Revolution, inspired in part by his writings, broke out.Though he was not actively involved in its planning or conduct, he ultimately approved of its goals which eventually led to Philippine independence.