Ancient cultures like Sates and Perans had lunar calendars without the concept of week as we understand it. Months were divided into smaller periods of time accordingly to lunar phases. With the adoption of 30-day months these were divided into two equal halves, the fortnights, of 15 days each. Later, when Sardens made further adjustments to the calendar, Perans created 5-day weeks by dividing the fortnights into 3 parts. The last step in the creation of the current Megadelanean week was to unite two Peran weeks into 10-day weeks, and adjusting them so each month had three weeks.
The names of days vary from language to language, but they are usually the result of naming days after deities or weekly tasks. The Hellesan names begin with di, which is the short form of Peran dinaki "24h day". The first five days have names of Peran origin, the oldest of all, and the last five are the new additions after the creation of 10-day weeks.
The days of the week are:
Dimarn "day of the Great Ones", from Peran dinaki Maremnas. Devoted to the Great deities of the Megadelanean pantheon, the so called 'Twelve'. It was the only truly festive day in Ancient days, and people named it, jockingly, dinaki Marnu "(the) Great Day". Nowadays it's one of the three festive days of the week. Dinçolà "day of the Home-ones; Day of the domestic ones". Devoted to the home deities and the ancestors. Originally it was a half-festive, and people spent the day cleaning the house and doing the other domestic tasks, so people jockingly referred to that day as dinaki tedule (day of (doing) the house), irreverent form of dinaki Tedulani. Didac "Idachi's Day". Dedicated to Idachi, one of The Twelve. Dinfers "Ferseu's Day", the national hero of Perans. Dinare "Niare's Day". Dedicated to Niari or Niare, the moon goddess. Disturs "rusturs' Day". Dedicated to the natural genies of forests, mountains and wild lands. Dirines "irines' Day". Dedicated to the genies of calm waters. Dibardes "pardenyes' Day". Dedicated to the genies of the land and the countryside. Dintarmes "tambres' Day". Dedicated to the genies of the underground. Dirols "erols' Day". Dedicated to the genies of the atmospheric skies.