The ${\mathrm{Ce}}_{(1\ensuremath{-}x)}{\mathrm{La}}_{x}{\mathrm{CrGe}}_{3}$ $(x=0, 0.19, 0.43, 0.58, \mathrm{and} 1)$ intermetallic compound system has been investigated by magnetization measurements and neutron scattering techniques to determine the effect of La doping on the magnetic ordering and exchange interaction between Cr ions. The structural and magnetic characterization in this series was first verified by x-ray diffraction and bulk magnetization measurements. The samples exhibit the known hexagonal perovskite structure ($P{6}_{3}/\mathrm{mmc}$ space group) and have a single magnetic phase according to magnetization measurements. In this paper, the ferromagnetic ordering temperature for Cr evolves smoothly from a range of 68 K to 77 K for ${\mathrm{CeCrGe}}_{3}$ to a range of 91 K to 96 K for ${\mathrm{LaCrGe}}_{3}$ as La replaces Ce. Magnetization results indicate the formation of domain walls below the transition temperature for all ${\mathrm{Ce}}_{(1\ensuremath{-}x)}{\mathrm{La}}_{x}{\mathrm{CrGe}}_{3}$ systems investigated. Neutron results indicate ordered magnetic Cr moments aligned along the $c$ axis for the $x=1$ ${\mathrm{LaCrGe}}_{3}$ system, as well as for $x=0.19$, 0.43, and 0.58, which contrasts with the $x=0 {\mathrm{CeCrGe}}_{3}$ where the moments order in the ab plane.