SPQR (the original title of the first book, until the sequels came out) is a Latin initialism for Senatus Populusque Romanus ("The Roman Senate and People"), the official name of the Republic.
Decius' companions include his slaves Cato, Cassandra, and Hermes; his friends, the Greek gladiatorial physician Asklepiodes and the gangster/politician Titus Annius Milo; and his staunch enemies, the siblings Clodia and Clodius.
In later books, Decius is betrothed and then married to the (fictional) niece of Caesar, Julia Caesaris.
The dates are all listed at the end of each book in the ab urbe condita calendar system.
In 2015, a German company had planned to adapt the series for TV,[1][2] however, they have withdrawn from the project in 2022 for financial reasons.