  The Hubbard model on an anisotropic triangular lattice in two dimensions, a
fundamental model for frustrated electron physics, displays a wide variety of
phases and phase transitions. This work investigates the model using the ladder
dual fermion approximation which captures local correlations non-perturbatively
but approximates non-local correlations. We find metallic, one-dimensional
antiferromagnetic, non-collinear antiferromagnetic, square-lattice
antiferromagnetic, and spiral phases but no evidence of collinear
antiferromagnetic order in different parts of the phase diagram. Analyzing the
spin susceptibility in detail, we see both regions of agreement and of
discrepancy with previous work. The case of Cs$_2$CuCl$_4$ is discussed in
detail.
