Who were they?
The Church Fathers were eminent people who lived in the early centuries of Christianity, usually the first eight Centuries. They were Christian bishops, priests, monks, teachers, theologians, and scholars who left writings that were the go-to sources for their successors, particularly about controversial issues. Many scholars and Churches, e.g., Orthodox and Catholic Churches, still study and use their writings until this day.
The New World Encyclopedia provides a brief introduction with a little paragraph about each father. Scholars categorise their writings by the time in history they lived. For example, the fathers who lived before in the Council of Nicaea were called Anti-Nicene Fathers. Among them are the Apostolic fathers who contacted the Holy Apostles in the first two centuries of Christianity.
The writings are further categorised by the geographical location where the writers were living. In 395 C.E., the Roman Empire was divided into two parts: the East and the West. And the fathers are categorised as Western or Eastern Fathers accordingly. Western fathers are sometimes called Latin Fathers, and Eastern fathers are sometimes called Greek Fathers. The geographical division is underpinned by schools of thought that these fathers followed. So, fathers from the Alexandrian School of thought, e.g., St. Athanasius of Alexandria, would provide a very different logic and argument on a similar topic explained by the fathers from the West, e.g., St. Ambrose of Milan. Sometimes Fathers from the East would argue differently on the same topic because they came from different Theological Schools, e.g. Antioch and Alexandria
What did they write about?
Their writings covered many topics including; bible commentary, Christian dogma, apologetics, Christian behaviour, and sermons on Church occasions (e.g. Christmas).
This is a list of some websites that provide a comprehensive list of their writings:
Christian Classics Etherial Library
This website is the most comprehensive of all, it is the result of a massive project in that most of the writings were compiled in volumes of books. The author divides the fathers by their historic period, then by writer.
Early Christian Writings
This website mostly lists the writings by the writer or the topic if the author is unknown.
This website is where to go if you want to search about a particular topic.
This one is a Catholic online encyclopedia, it lists the writings by the author than by the title of the document.
This is a well-known British library website. It provides a list of some of the western fathers’ writings.