The markings on this shield are consistent with those of a knight from the Hospitaller medieval catholic military order which developed in the early 12th century. The order started with the aim of providing care for sick, poor or injured pilgrims and developed into a military religious order acting in defense of the Holy Land. Reference https://en.wikipedia.org/wiki/Knights_Hospitaller
The model was made in Zbrush and textures added in Substance Painter. The download includes an STL file for 3d printing with all surface details baked into the geometry - choose 'additional file' at download. For the textured model displayed here choose 'orginal format'.
As with all of my models you are free to use it in any way.