Wavy background #2022
Blue CC 0CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
More Textures
Background pattern 306 (colour 5) #1879
Colorful CC 0Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Tiny Grid@2X #892
Light CC BY-SA 3.0You know, tiny and sharp. I’m sure you’ll find a use for it.
Source Atle Mo
Background pattern blue #1940
Blue CC 0Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
Tree Bark #1182
Light CC BY-SA 3.0This one is something special. I’d call it a flat pattern, too. Very well done, sir!
Source GetDiscount
Background pattern 224 (colour 4) #2339
Colorful CC 0To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Decorative divider 194 #2478
Dark CC 0From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
3D Wood #1475
Wood CC 0Basket Fibers, Basket Texture, Braid Background style CC0 texture.
Source 1A-Photoshop
WaveCut@2X #76
Light CC BY-SA 3.0If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
Prismatic Floral Background No Black@2X #476
Light CC 0Prismatic Floral Background No Black
Source GDJ
Floral design 100 (version 2) #1773
Dark CC 0From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Pinetree in tortoiseshell(亀甲松) #2538
Dark CC 0The image depicts a seamless pattern of Japanese Edo pattern called "kikkou-matsu" or "亀甲松" meaning " tortoiseshell-pinetree".The real pinetree is like this: https://jp.pinterest.com/pin/500744052301065077/
Source Yamachem
Felt@2X #301
Wall CC BY-SA 3.0Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Textured Orange Stripe Pattern #997
Stripes CC BY-SA 3.0A textured orange background pattern with vertical stripes.
Source V. Hartikainen