Mary Reed & Eric Mayer
John the Eunuch, Lord Chamberlain to the Emperor Justinian in Constantinople in 537:

One for Sorrow (1999) [review]

Two for Joy (2000)

Three for a Letter (2001)

Four for a Boy (2003)
Finalist 2004 Bruce Alexander Award

Five for Silver (2004)
Finalist 2005 Bruce Alexander Award

Six for Gold (2005)

Seven for a Secret (2008)

Eight for Eternity (2010)

Nine for the Devil (2012)

Ten for Dying (2014)

Murder in Megara (2015)

Written as Eric Reed (joint pseudonym of Mary Reed & Eric Mayer)
Grace Baxter, a village constable’s daughter beginning in in 1941 Britian:

The Guardian Stones (2016)

Ruined Stones (2017)