Your question on the political and economic factors that influence the production and content of textbooks is an important one. This subject comes up within homeschooling communities and is well worth examining. The bottom line is that, in the United States, textbooks are a commodity meant to earn profit. As such, information presented as fact in textbooks can be subject to bias designed to make the product more accepted by a given market.
Here is a link to a great journal article that addresses your question in some detail. It is entitled “Textbook Publishing: The Political and Economic Influences,” by Michael W. Apple.
In this article, Professor Apple refers to textbooks as an “economic commodity … subject to the intense competition and the pressures of profit.” He goes on to explain that “the textbook is not only an economic product, it is political as well.”
After all, the textbook industry is just that—an industry. If the information presented in the books does not conform to the expectations and sensibilities of a particular audience, the books will not sell. By audience I do not mean the students, but the boards of education (or other committees) responsible for selecting the textbooks. To find out who selects textbooks across the states, refer to this link from the Education Commission of the States (ECS).
Sometimes the content of textbooks is influenced by governments that wish to show themselves in a certain light to present and future generations. Although you will be able to readily find a number of articles on how Japanese school textbooks have downplayed events related to the Empire of Japan during World War II, or how the Chinese government regulates textbooks, it is important to also recognize that textbooks in our own country have at times presented a version of history tailored to a particular societal “myth” that serves a political purpose. What comes to mind is the omission or watering down of the facts and realities of Native American genocide, along with and African slavery, in generations of history textbooks.
For specific examples of how textbook content varies in order to appeal to different geographically-based markets across the United States, you will not want to miss an article in The New York Times (January 20, 2020) entitled “Two States. Eight Textbooks. Two American Stories,” by Diana Goldstein, which states: “American history textbooks can differ across the country, in ways that are shaded by partisan politics.” Here is a link to this article.
For another example of how politics (as connected to the religious beliefs of large segments of a voting population) influence classroom teaching content, have a look at the following article in The Atlantic on the omission of evolution as a scientific concept in some Texas public high schools. It is interesting to know why some people favored this approach while others did not.
I would also recommend looking at your question from the point of view of how the economic conditions of a particular community limit textbook choices. Public schools in the United States depend, at least in part, on revenue generated from local property taxes. As a result, poor communities are more likely to use “outdated textbooks in short supply,” as stated by the American Psychological Association in the following article: