Nicely executed tiling for an interesting pattern.
Source Ignasi Àvila Padró
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Gold Triangular Seamless Pattern No Background
Source GDJ
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Seamless pattern the basic tile for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Small dots with minor circles spread across to form a nice mosaic.
Source John Burks