The Norwegian language conflict (Norwegian: språkstriden, Danish: sprogstriden) is an ongoing controversy in Norwegian culture and politics about the different varieties of written Norwegian. From 1536/1537 until 1814, Danish was the standard written language of Norway due to the union of crowns with Denmark. As a result, the proximity of modern written Norwegian to Danish underpins controversies in nationalism, rural versus urban cultures, literary history, diglossia (colloquial and formal dialects, standard language), spelling reform, and orthography.

In the United Kingdoms of Denmark and Norway, the official languages were Danish and German.^{[citation needed]} The urban Norwegian upper class spoke Dano-Norwegian (dansk-norsk) (Danish, with Norwegian pronunciation and other minor local differences), while most people spoke their local and regional dialect. After the Treaty of Kiel transferred Norway from Denmark–Norway to Sweden–Norway in 1814, Dano-Norwegian (or "det almidelige bogmaal") was the sole official language until 1885 when Ivar Aasen's Landsmaal gained recognition.

In the early 1840s, young linguist Ivar Aasen traveled the countryside gathering up the words and grammar used there. He assembled a Norwegian language based on dialects little affected by Danish and published his first grammar and dictionary of the Norwegian people's language (Folkemål), in 1848 and 1850 respectively. He and many other authors wrote texts in their own dialects from around this time.

Norwegian is a North Germanic language. Dano-Norwegian, which began as a tongue readily accessible to (and essentially written as) Danish, took in increasing amounts of Norwegian. Meanwhile, Aasen's "people's language" became established. Parliament decided in 1885 that the two forms of written Norwegian were to be equally official. Both went through some name changes until 1929, when parliament decided that the one originally based on Danish should be called Bokmål (literally "book language") and the one based on Norwegian dialects should be called Nynorsk ("new Norwegian").

In the early 20th century, a more activist approach to written Norwegian was adopted. The government attempted over several decades to bring the two language forms closer to each other with the goal of merging them but failed due to widespread resistance from both sides. The now-abandoned official policy to merge Bokmål and Nynorsk into one written standard called Samnorsk through a series of reforms has created a wide spectrum of varieties of the two. An unofficial form called Riksmål is considered more conservative than Bokmål. Similarly, the unofficial Høgnorsk is much closer to Aasen's mid-1800s language than to today's Nynorsk. Norwegians are educated in whichever form is more widespread where they live (hovedmål/hovudmål) and the resultant secondary language form (sidemål, "side language").

There is no officially sanctioned spoken standard of Norwegian, but according to some linguists, like Kjell Venås, one de facto spoken standard is akin to Bokmål, Urban East Norwegian (Standard øst-/austnorsk).

The earliest examples of non-Danish Norwegian writing are from the 12th century, with Konungs skuggsjá being the prime example. The language in use at this time is known as Old Norse, and was widely used in writing in Norway and Iceland. The languages of Sweden and Denmark at this time were not very different from that of Norway, and are often also called Old Norse. Although some regional variations are apparent in written documents from this time, it is hard to know precisely the divisions between spoken dialects. This interim Norwegian is known as middle Norwegian (mellomnorsk).

With the Black Death in 1349, Norway's economy and political independence collapsed, and the country came under Danish rule. The Norwegian language also underwent rather significant changes, shedding complex grammatical forms and adopting a new vocabulary.