The phrase "as was common" is often used to indicate that something happened frequently or routinely. There are many synonyms for this phrase that can be used to add variety and nuance to your writing. Some possible alternatives include "as was typical," "in keeping with tradition," "as per usual," "as was expected," "in line with custom," "as was the norm," "as was customary," and "in accordance with convention." By using these synonyms, you can express the same basic idea in different ways and avoid repeating the same phrase over and over again. Consider using a thesaurus to help you find the right synonym for your specific context.