The Last Yankee in the Pacific

In the Winter 2004 issue of American Speech (Project Muse subscription required) two dialectologists, Daniel Long of Tokyo Metropolitan University and Peter Trudgill of the University of Fribourg, have traced the linguistic heritage of an English-speaking native of Japan's Bonin Islands back to a very distinctive accent found only in eastern New England.

ABSTRACT: On the isolated Bonin (Ogasawara) Islands in the western Pacific Ocean, the English language has been in use for close to two centuries. The first human residents arrived in 1830, and one individual from Massachusetts, in particular, left his progeny and his mark on island society. In this paper, we analyze tape recordings made in the 1970s of a speaker born (in 1881) and raised on the islands and demonstrate that his vowel system remarkably resembles that of Eastern New England, in particular that he maintains a phonemic distinction between NORTH and FORCE vowels. We discuss other conservative dialect features of his speech, such as a nonlabiodental variant of /v/ ([ß]) [like the Spanish /v/], which appears in complementary distribution with the mainsteam [v] variant, and contact features, such as th-stopping [i.e. th sounds like t or d]. In order to place this language variety, this speaker, and these recordings within their sociohistorical context, we provide a description of these unique islands and their complex linguistic heritage.

Here's one of the key pieces of evidence: the vowel distinctions or lack thereof among LOT, THOUGHT, NORTH, FORCE (or stock, stalk, stork, store). (I've replaced phonetic symbols with lay equivalents: ɔ = aw, ə = uh.)

Conservative General American: LOT ≠ THOUGHT ≠ NORTH [awr] ≠ FORCE [or]
Modern General American: LOT ≠ THOUGHT ≠ NORTH = FORCE [awr]
Canadian: LOT = THOUGHT [a] ≠ NORTH = FORCE [or]
Scots: LOT = THOUGHT [aw] ≠ NORTH [awr] ≠ FORCE [or]
Conservative RP ("Received Pronunciation"): LOT [a] ≠ THOUGHT = NORTH [aw] ≠ FORCE [awuh]
Modern RP ("Received Pronunciation"): LOT ≠ THOUGHT = NORTH = FORCE [awh]
Eastern New England: LOT = THOUGHT = NORTH [a] ≠ FORCE [awuh]
19th-Century Bonin English: LOT = THOUGHT = NORTH [a] ≠ FORCE [owuh]