The Nordic countries, especially Finland, played an un-proportional role in the early emergence of today´s ubiquitous mobile communications, as elucidated in extant research. This historical case study, part of broader research, concerns internationalisation of Finland´s early mobile telephony industry that in the 1970s to 1980s essentially consisted of the national PTT organisation PLH, realising the successful mobile telephone services ARP and NMT, and the dominant mobile phone manufacturer Salora SRP/Mobira, the predecessor of Nokia Mobile Phones. The aim is to gain deeper understanding of that process by interpreting the compiled historical account of that industry in the 1960s to 1980s in light of the assembled frame of internationalisation theories. The substantive part of the study first compiles the pertinent history of what was known as PLH between 1927 and 1989, with roots in Grand Duchy Finland under Russian Empire and the Crimean War in the 1850s. Then it does the same regarding Salora SRP/Mobira with much shorter history. The interpreted findings coined in four propositions suggest internationalisation paths with accidental and intentional stages punctuated with significant interactions in the 1970s to 1980s, not fully explained by the invoked theories.