Carl Friedrich Weierstrass was a German mathematician born on October 31, 1815, in Ostenfelde, Germany. He is often referred to as the "father of modern analysis" for his significant contributions to the field, particularly in the development of calculus and the theory of functions. Weierstrass introduced the concept of uniform convergence and formulated the Weierstrass approximation theorem, which states that any continuous function can be approximated by polynomial functions. Weierstrass also made important advancements in the study of complex functions and introduced the Weierstrass function, which is a classic example of a continuous function that is nowhere differentiable. His work laid the groundwork for many areas of mathematics, influencing later mathematicians such as Henri Poincaré and David Hilbert. Weierstrass passed away on February 19, 1897, leaving a lasting legacy in mathematical analysis.