Efficient generation of 1.5 um wavelength light has applications for ranging and remote sensing while being in the "eye safe" region of the optical spectrum. Diamond Raman lasers are excellent candidates for light sources at these wavelengths due to the excellent optical and mechanical properties of diamond as a laser material. This thesis describes the design and build of a MOPA fiber laser system in the CW regime as a pump for a Diamond Raman laser along with a design for operating it in the pulsed regime as well. The CW fiber laser was tested up to 200 W average power and characterized for each stage of the MOPA architecture. The third and final amplifier stage uses an extra large mode area(XLMA) fiber for decreasing irradiance of the signal with in the fiber and thus mitigating the unwanted nonlinear effects at the output when the system will be pulsed. Engineering designs will be presented for fiberized components that reduce the amount of passive fiber in the system overall. The process of putting end caps on the fiber facets will also be described. The multimode nature of the XLMA fiber required mode mixing elements to obtain a more uniform flat top beam profile. Characterization of the mode mixing fiber will be presented along with the output profile improvement.