The life and death of Texas German takes a detailed look at how Texas German came into being with German immigration to Texas, as well as how the declining use of Texas German in the past century has affected the language and its speakers. Boas gives an account of German Sprachinseln, or “speech islands,” around the world in order to give some context for his further discussion of Texas German. Also included is discussion on possible donor dialects for Texas German. While much of Boas’ discussion laments the fact that records from the era of initial settlement (1845–1850) often are not sufficiently specific about the areas of Germany in which immigrants originated, he notes that the Hessen-Nassau area likely contributed a large number of speakers. Boas consistently argues that Texas German differs in many ways from Standard German not because of its declining use, but because it has undergone several natural innovations paralleled by German dialects in several other areas.

Boas details the process of koinéization in Texas German from the initial influx of German settlers in the late 1840s through its current state of declining use, which began in the 1960s. Throughout his book, Boas argues that Texas German never underwent a final “focusing” stage, in which a dialect settles on a consistent pattern of phenomena (which is distinct from early stages, which display significant interspeaker variability). Boas provides a number of dialect maps of Germany, showing the pronunciation of several representative words for the various donor dialects that went into the creation of Texas German. Boas gives numerous examples of specific phonological and morphosyntactic developments in Texas German, providing ample and detailed data. One point Boas brings up is that Texas German, while arguably not a cohesive dialect overall, has retained its historical phonological and morphological features while undergoing a decline in usage. He notes that Texas German seems to have remained relatively unchanged throughout the process of language death, and that modern Texas German has not undergone many significant changes since the 1800s, when it was the dominant language in New Braunfels.

Boas comments on the impending death of Texas German and the possibility of language maintenance. He discusses the considerable prestige that the language enjoyed in its early days, when significant parts of Texas were entirely German-speaking, and how such prestige steadily declined as Texas became more and more English-speaking. Based on the questionnaires Boas gave to his consultants, the tendency for parents not to teach their children Texas German seems to stem from the belief that Texas German is not a useful language. Boas’ book is eminently readable and clearly written, presenting a valuable introduction to Texas German for the nonexpert, as well as giving useful commentary on language death in general.