During the 17th and 18th centuries, Estonian inflection was described in the traditional framework of Latin grammar. Grammars still differed from one another. For example, Johann Gutslaff observed that the case forms which were traditionally included in the Latinized case paradigm and other Estonian word forms were actually formed the same way. Johann Hornung’s grammar started a new era by offering a more vernacular-based description of Estonian inflection than in previous grammars. An active search for alternative ways to describe Estonian inflection took place in the first half of the 19th century. Both verbal and nominal paradigms received novel interpretations, and mutation was for the first time treated systematically. The nature of case and the contents of the case paradigm were the most popular topics. The first complete overview of the Estonian inflectional system which followed the new ideas was compiled by Eduard Ahrens. In the second half of the 19th century, the thorough descriptive grammar by Ferdinand Johann Wiedemann and the first grammars in the Estonian language were published. The first disciplines of emerging Estonian linguistics, historical linguistics and dialectology evolved during the 1920s–1930s under the leadership of Andrus Saareste, Julius Mägiste and others. The 1940s–1950s were shadowed by war and the beginning of the Soviet occupation. Linguistic research was neither particularly productive nor novel, and the fields and methods remained largely the same as before. Arnold Kask began his thorough studies on the history of literary Estonian, which in time developed into a fruitful research discipline under his influence. The 1960s–1990s was a period characterized by intensive attention to inflection theory. First, Estonian word forms were described using the internationally well-known IA and IP models. Then, Ülle Viks, Toomas Help, Henn Saari and Martin Ehala all developed their own morphological models. Research was influenced by novel methods and insights, e.g. the theory of natural morphology and the center-periphery view of linguistic phenomena. Huno Rätsep suggested a new interpretation of Estonian moods, giving evidentiality a distinctive role. Toomas Help and Joel Nevis examined some case morphemes as clitics instead of the traditional interpretation as case affixes. A thorough descriptive grammar was compiled (1993-1995). Its inflection chapter, authored by Kristiina Ross, differed radically from the previous grammars and relied on the morphological classification of Ülle Viks and the model of regular and irregular morphology by Toomas Help. Some new disciplines emerged: first-language acquisition, the study of colloquial language and computational linguistics. The research of Mati Hint, in particular, revealed major systematic differences between formal and colloquial inflection. Traditional disciplines flourished as well. Among other works, many important general treatments were published: a history of the noun paradigm by Huno Rätsep, a history of literary Estonian by Arnold Kask, a systematic overview of contemporary inflection by Jaak Peebo and comprehensive overviews of several Estonian dialects. The most important theoretical works of the new millennium include the descriptions of Estonian verb and noun inflection using the WP model by James Blevins. Studies on colloquial Estonian have revealed some ongoing changes in morphological paradigms. Second-language acquisition and the study of language disorders have developed into full-fledged research areas. Of the existent disciplines, first-language acquisition, dialectology, the history of literary Estonian and research on colloquial Estonian have been productive. Diachronic inflection, on the other hand, has received less attention than before. Recently, research on morphosyntax has prevailed over the study of inflection.