In order to understand St Francis and how he got to be famous, look at St Cosmo and St Damiano because Francis used to pray in a church dedicated to them. The story of these two saints who are not widely known is detailed in many scholarly papers on sites like academia.edu and researchgate for those who are interested. (To cite just one single example, a hematologist was intrigued by the survival of a leukemia patient and her studies of Medical miracles is reviewed on oxford academic, in 2014. This is not to promote this study over or against any other, but rather to show that the topic is scholarly and not "merely" spiritual. And, sometimes evangelizing is lifesaving, see pic:They were a doctor and a pharmacist who offered their services for free and were executed by the Roman Empire because of it. As Ciccio Carere notes, at trial, the proconsul required them to "A Cristo rinnegare", but they refused.
There are also popular festivals dedicated to these saints in places like Riacci, and the 100th anniversary of this festival dedicated to these two saints will be celebrated in Boston this year by the Mediterranean diaspora in the area. There is a mission church established in 2015 in Brooklyn dedicated to these saints, Since 2020 this church has been staffed by the Shalom community.There is a "Lot" radio station broadcasting in front of the church as well which has been there since around the time the mission came to be.