Diamond pattern (colour 6) #2280
Yellow CC 0From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
More Textures
Noisy Grid@2X #960
Gray CC BY-SA 3.0This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
Aged Paper Background Tile #1074
Paper CC BY-SA 3.0A seamless background tile of aged paper with shabby look.
Source V. Hartikainen
Decorative divider 236 #2090
Dark CC 0From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Prismatic Snowflakes Pattern No Background #411
Light CC 0Prismatic Snowflakes Pattern No Background
Source GDJ
Background pattern 268 #2066
Dark CC 0Remixed from a drawing in 'Kulturgeschichte der Deutschen im Mittelalter' Franz von Loeher, 1891. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
Dark Brick Pattern #1032
Stone CC BY-SA 3.0A seamless pattern of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
Floral pattern 13 #1756
Green CC 0From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Patterned metal plate 7 #2556
Metal CC 0From an image on opengameart.org shared by rubberduck.
Source Firkin