which had their own village sign language. Other students brought knowledge of their own home signs. Laurent Clerc, the first teacher at ASD, taught using French Sign Language (LSF), which itself had developed in the Parisian school for the deaf established in 1755. From that situation of language contact, a new language emerged, now known as ASL. More schools for the deaf were founded after ASD, and knowledge of ASL spread to those schools. In addition, the rise of Deaf community organizations bolstered the continued use of ASL. Societies such as the National Association of the Deaf and the National Fraternal Society of the Deaf held national conventions that attracted signers from across the country. All of that contributed to ASL's wide use over a large geographical area, atypical of a sign language. While oralism, approaches to educating deaf students focusing on oral language, had previously been used in American schools, the Milan Congress made it dominant and effectively banned the use of sign languages at schools in the United States and Europe. However, the efforts of Deaf advocates and educators, more lenient enforcement of the Congress' mandate, and the use of ASL in religious education and proselytism ensured greater preservation and documentation that European sign languages, albeit more influenced by fingerspelled loanwords and borrowed idioms from English as students were societally pressured to acheive fluency in spoken language. Nevertheless, oralism remained the prominent method of deaf education up to the 1950s. Linguists did not consider sign language to be true "language" but as something inferior. Recognition of the legitimacy of ASL was achieved by William Stokoe, a linguist who arrived at Gallaudet University in 1955 when that was still the dominant assumption. Aided by the Civil Rights Movement of the 1960s, Stokoe argued for manualism, the use of sign language in deaf education. Stokoe noted that sign language shares the important features that oral languages have as a means of communication, and even devised a transcription system for ASL. In doing so, Stokoe revolutionized both deaf education and linguistics. In the 1960s, ASL was sometimes referred to as "Ameslan", but that term is now considered obsolete. Population Counting the number of ASL signers is difficult because ASL users have never been counted by the American census. The ultimate source for current estimates of the number of ASL users in the United States is a report for the National Census