Background pattern 306 (colour 5) #1879
 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
White Paperboard #374
 Fabric  CC BY-SA 3.0

Could be paper, could be a Polaroid frame – up to you!

Source Chaos

Background pattern 203 #2486
 Brown  CC 0

A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

“Transparent” Background Pattern@2X #494
 Light  CC 0

An emulated “transparent” background pattern, like that of all kinds of computer graphics software.

Source AdamStanislav

Floral background 2 #380
 Wall  CC 0

Background formed from the original with an emboss effect

Source GDJ

Paper 2 #21
 Paper  CC BY-SA 3.0

New paper pattern with a slightly organic feel to it, using some thin threads.

Source Atle Mo

Background pattern 221 #2347
 Dark  CC 0

A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 66@2X #478
 Wall  CC 0

A background pattern drawn in Inkscape.

Source Firkin

Prismatic Octagonal Background@2X #440
 Noise  CC 0

Prismatic Octagonal Background

Source GDJ

Background pattern 252 (colour 4) #2159
 Light  CC 0

Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Checkered Light Emboss@2X #281
 Grid  CC BY-SA 3.0

Sort of like the Photoshop transparent background, but better!

Source Alex Parker

Background pattern 220 #2360
 Dark  CC 0

A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Derived from a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.

Source Firkin