Your edits to Succession of the Roman Empire seem credible but they really need to be supported by citation. See WP:citing sources if you want to format it nicely though it is ok to do a very simple book or web page reference enclosed in <ref> ... </ref> tags and someone will smarten it up later. (That's the easy bit: the hard part of contributing to wikipedia is finding an appropriate range of sources. Again, welcome. 𝕁𝕄𝔽 (talk) 21:12, 13 April 2023 (UTC)[reply]
Unfortunately, Wikipedia articles are not valid citations (WP:Wikipedia is not a reliable source). Maybe those articles have the citations needed and can be "borrowed" from them but the responsibility lies with you as contributing editor to find the supporting citations for material you add. If you need help with writing citations, do let me know or ask at the WP:Teahouse. --𝕁𝕄𝔽 (talk) 10:46, 14 April 2023 (UTC)[reply]