From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
He influenced us all. “Don’t be sad because it’s over. Smile because it happened.”
Source Atle Mo
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Geometric lines are always hot, and this pattern is no exception.
Source Listvetra
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
A seamless design of flowers remixed from a jpg on Pixabay by Prawny.
Source Firkin
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
The image depicts a seamless pattern of the design which includes a stylized lotus and a stylized crane.I referred to the original image in a book which is into public domain.
Source Yamachem
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev