Answer by taking a quote from the following article:

The Naga people (pronounced [na:ga:]) are an ethnic group conglomerating of several tribes native to the North Eastern part of India and north-western Myanmar (Burma). The tribes have similar cultures and traditions, and form the majority ethnic group in the Indian state of Nagaland, with significant population in Manipur, Arunachal Pradesh and in Assam. The Naga speak various distinct Tibeto-Burman languages, including Anal, Angami, Ao, Chakhesang, Chang, Lotha, Mao (Emela), Maram, Phom, Pochuri, Poumai (Poula), Phom, Rengma, Rongmei (Ruangmei), Sangtam, Sumi, Tangkhul, Thangal and Zeme. In addition, the Naga have developed Nagamese Creole, which they use between various indigenous communities and villages, which each have their own dialect of language.

Nagas have more language diversity than any other ethnic group or states in India. Naga people speak over 89 different languages and dialects, mostly unintelligible with each other. However, there are many similarities in between different languages spoken by them. Per Grierson's classification system, Naga languages can be grouped into Western, Central and Eastern Naga groups. The Western group includes among others Angami, Chokri, Khezha and Rengma. The Central Naga group includes Ao, and Lotha ; while Eastern group includes Konyak, Phom, Sangtam, Khiamniungan, Yimchunger and Chang tribes. The Sumi group originating in both central and western parts. In addition, there are Naga-Bodo group illustrated by Mikir language, and Kuki group of languages illustrated by Sopvama (also called Mao Naga) and Luppa languages. These mostly belong to the Tibeto-Burman language group of the Sino-Tibetan family of languages. Shafer came up with his own classification system for languages found in and around Nagaland.  The diversity of languages and traditions of the Nagas results most likely from the multiple cultural absorptions that occurred during their successive migrations. According to legend, before settling in the region, these groups moved over vast zones, and in the process, some clans were absorbed into one or more other tribes. Therefore, until recent times, absorptions were a source of many interclan conflicts.  In 1967, the Nagaland Assembly proclaimed English as the official language of Nagaland and it is the medium for education in Nagaland. Other than English, Nagamese, a creole language form of the Assamese language, is a widely spoken language. Every tribe has its own mother tongue but communicates with other tribes in Nagamese or English. However, English is the predominant spoken and written language in Nagaland.

What was the impact of the different languages spoken?
The diversity of languages and traditions of the Nagas results most likely from the multiple cultural absorptions that occurred during their successive migrations.