From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
This seamless pattern consists of a blue grid on a yellow background.
Source V. Hartikainen
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
This is the remix of "Background pattern 115" uploaded by "Firkin".Thanks.
Source Yamachem
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
This one needs to be used in small areas; you can see it repeat.
Source Luca
Seamless Prismatic Geometric Pattern With Background
Source GDJ
Prismatic Groovy Concentric Background 3
Source GDJ
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Prismatic Polyskelion Pattern No Background
Source GDJ
More in the paper realm, this time with fibers.
Source Jorge Fuentes