Electronic Journal of Differential Equations, Vol. 2021 (2021), No. 80, pp. 1-22. Title: A fractional Gronwall inequality and the asymptotic behaviour of global solutions of Caputo fractional problems Author: Jeffrey R. L. Webb (Univ. of Glasgow, Glasgow, UK) Abstract: We study the asymptotic behaviour of global solutions of some nonlinear integral equations related to some Caputo fractional initial value problems. We consider problems of fractional order between 0 and 1 and of order between 1 and 2, each in two cases: when the nonlinearity depends only on the function, and when the nonlinearity also depends on fractional derivatives of lower order. Our main tool is a new Gronwall inequality for integrals with singular kernels, which we prove here, and a related boundedness property of a fractional integral of an $L^1[0,\infty)$ function. Submitted July 23, 2021. Published September 20, 2021. Math Subject Classifications: 34A08, 34A12, 26A33, 26D10. Key Words: Fractional derivatives; asymptotic behaviour; Gronwall inequality; weakly singular kernel.