In the 5th century the Indian mathematician Aryabhata (476-499) wrote a small but famous work on astronomy, the Aryabhatiya. This treatise, written in 118 verses, gives in its second chapter a summary of Hindu mathematics up to that time. Two hundred years later, an Indian astronomer called Bhaskara glossed this mathematical chapter of the Aryabhatiya.An english translation of Bhaskara's commentary and a mathematical supplement are presented in two volumes.Subjects treated in Bhaskara's commentary range from computing the volume of an equilateral tetrahedron to the interest on a loaned capital, from computations on series to an elaborate process to solve a Diophantine equation.This volume contains an introduction and the literal translation. The introduction aims at providing a general background for the translation and is divided in three sections: the first locates Bhaskara's text, the second looks at its mathematical contents and the third section analyzes the relations of the commentary and the treatise.