Gender gaps and geographical imbalances on Wikimedia are already well-researched. Our focus is a cultural gap which does not correspond exactly to geography. For example, on the English Wikipedia, List of sculptors is 99% Western, despite sculpture being common to many different cultures, Lists of painters by nationality is around 75% European, and List of contemporary artists is 80% European. Many countries with especially rich artistic traditions, such as Libya and Mali, do not even have dedicated articles about their art (in the same way as there exist exhaustive articles such as French art or Greek art). The English Wikipedia's Level-4 Vital Article list for visual artists currently includes six from non-Western cultures, out of 124 articles.
On Commons, the Gallery of Non-Photographic Media – Religious Art showcases ninety pieces of art relating to Christianity, alongside eight images for Buddhism, five for Judaism, five for Hinduism, and three for Paganism. Islam, with around two billion followers worldwide, has three examples of religious art (two of which we've uploaded).
It's unequivocally a good thing that Wikimedia projects make so much knowledge about art freely available. Our concern is that its overwhelming focus on the Western canon gives readers a misleadingly narrow picture of visual art and its role in human cultures. It's great that there are extensive articles about John Constable or the Bayeux Tapestry in English; we just want similar recognition for the artists or works from different cultures that are at least as important to those cultures as Constable is to British culture: Shibata Zeshin in Japan, or Raden Saleh in Indonesia, for example.
The Wikidata project Sum of All Paintings is extremely impressive in how it has drawn together details of more than 600,000 paintings from thousands of catalogues. While praising it, we have to be aware that a focus on paintings, usually by named artists, is itself a kind of bias towards European culture. The most celebrated art within another culture might be textile art, architectural features, or calligraphy; we should document these as well.