The phrase "existed from" refers to the time or period during which something has been present or available. Alternatives to this phrase would depend on the context in which it is used, but some options include "originated in," "began in," "emerged from," "stemmed from," "had its roots in," or simply "started with." These synonyms provide a better understanding of when or how something came to be and offer clarity to the reader. It is important to choose the appropriate word or phrase to accurately convey the intended meaning and create a cohesive and informative piece of writing.