  In this paper, first we introduce the notion of a nonabelian embedding
tensor, which is a nonabelian generalization of an embedding tensor. Then we
introduce the notion of a Leibniz-Lie algebra, which is the underlying
algebraic structure of a nonabelian embedding tensor, and can also be viewed as
a nonabelian generalization of a Leibniz algebra. Next using the derived
bracket, we construct a differential graded Lie algebra, whose Maurer-Cartan
elements are exactly nonabelian embedding tensors. Consequently, we obtain the
differential graded Lie algebra that governs deformations of a nonabelian
embedding tensor. Finally, we define the cohomology of a nonabelian embedding
tensor and use the second cohomology group to characterize linear deformations.
