The academic journal publishing scene is largely dominated by large commercial publishers based in Western countries, indexed in citation databases such as Scopus and Web of Science that reflect the bias towards these countries, sources and languages (especially English).
The issue is compounded by the research ecosystems in countries like the UK which seemingly reward publication in the elite of top-ranked academic journals.
Further damage was inflicted by the efforts of Jeffrey Beall and others to expose predatory journal publishing practices. Whilst their motivations may have been well intentioned, it is not difficult to find examples where this has directly discriminated against the efforts of genuine scholarly publishers, particularly in developing countries.
There are many options for anyone looking to supplement (or replace) the dominant article resources we have become so dependent upon with potential alternatives. Aside from the well-known Directory of Open Access Journals (DOAJ), the content of which reflects much less of a bias towards Europe and North America, a good starting point is:
Area Studies subject guide - offers many links to full text journals and indexing/abstracting services for regions and countries beyond Europe and North America
Preprints - essentially draft articles (like working papers) and therefore not peer reviewed (but usually moderated) - are widely available, and some services are trying to harvest these from a wider range of countries. For example, the Open Science Framework OSF Preprints includes preprints from Africa, India, and the Middle East.
JSTOR has curated a range of reading lists (comprising books as well as journal articles), many of which are connected to decolonisation topics.
For the colonial period, consult some of the resources listed on the subject guides (Area Studies, History, Politics, Sociology) and the Special Collections & Archives page on this guide. Here is an example of some of the interesting research being done on periodical publications from this period: