That we know of, Paul never visited Colossae. At one time, it had been a thriving metropolis in Asia Minor. But time, earthquakes, and the building of the city of Laodicea not far away contributed to Colossae’s demise.
The Church in Colossae was probably founded by Epaphras (see Colossians 1:3-8), but one of its members was the household of Philemon.
The problem plaguing the Colossian church was one of spirituality. Like our own time, there were those who believed that feelings, supernatural experiences, visions and revelations, and religious asceticisms (eg. dietary laws) contributed to a closeness with God. Like our own time, these beliefs led to forms of religion that made people “feel” holy and religious, without paying attention to what God actually said or required.
As he begins his letter, Paul moves straight away to the most important thing: Jesus. In all things, he must have supremacy. What he said, how he lived, what he and his heavenly Father require, the relationship they build, all is of supreme importance.
Modern spirituality is a pagan invention. It presumes one can build a relationship with God. No one can. The only relationship anyone can have with God is the one God gives freely through His son. The terms of that relationship are dictated by God. Anything else is not spirituality, but folly.
Chapters one and two of Colossians make this point plain. Chapters three and four make equally plain what this relationship looks like in our daily living.