The image depicts an edo-era pattern called "same-komon" or "鮫小紋"which looks like a shark skin.The "same" in Japanese means shark in English.
Source Yamachem
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Prismatic Geometric Pattern Background No Black
Source GDJ
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
The name alone is awesome, but so is this sweet dark pattern.
Source Federica Pelzel
Prismatic Polyskelion Pattern No Background
Source GDJ
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
A repeating graphic with ancient pattern. I came up with this name/title at last minute, so you may find that there is very little of ancientness in this pattern after all.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
A seamless background pattern with a texture of wood planks. This wood background pattern has vertically arranged planks. You may try to rotate it 90°, to see how it will look like when the wood planks are arranged horizontally.
Source V. Hartikainen
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
A repeating background of beige (or is it more vanilla yellow) textured stripes. One more background with stripes.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
A seamless paper background colored in pale yellow.
Source V. Hartikainen
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod