Background pattern 306 (colour 4) #1877
 Colorful  CC 0

Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.

Source Firkin

 More Textures
Floral Pattern Background 3 #218
 Noise  CC 0

PDP

Source GDJ

Tileable Wave Pattern 2 remix #2490
 Dark  CC 0

This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.

Source Yamachem

Decorative divider 228 #2154
 Dark  CC 0

Remixed from a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.

Source Firkin

Floral design 91 #1814
 Dark  CC 0

From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.

Source Firkin

Seamless Wood Pattern #889
 Wood  CC BY-SA 3.0

A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.

Source V. Hartikainen

Diamond pattern (colour 8) #2273
 Red  CC 0

From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Abstract Arbitrary Geometric Background #497
 Noise  CC 0

Abstract Arbitrary Geometric Background derived from an image on Pixabay.

Source GDJ

Prismatic Dots Background 4 #507
 Noise  CC 0

Prismatic Dots Background 4

Source GDJ

Seamless Prismatic Pythagorean Line Art Pattern No Background #569
 Light  CC 0

Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).

Source GDJ

Dark Denim #29
 Dark  CC BY-SA 3.0

A dark denim looking pattern. 145×145 pixels.

Source Atle Mo