The grammar structure ことから is used to express a reason or basis derived from an observable fact or characteristic. It translates to "from the fact that," "because," or "due to the fact that." Unlike the simple causal から, ことから emphasizes that the reason is grounded in a concrete, recognizable fact or piece of evidence.
ことから is used when stating a logical conclusion or judgment based on something that can be observed or known.
One of the most characteristic uses of ことから is to explain why something is called a certain name or how a name originated. This is very common in written explanations and descriptions.
ことから carries a somewhat formal or explanatory tone and is frequently found in written Japanese, news articles, and informational texts. In casual conversation, simply using から is more natural.