Sextilis to Sept

I quit the days that chill us

As we March toward Sextilis

Romulus intercalated the year

Adding dual moons, factitious

***

Sex became Octigenti

And Sept, Novem a'plenty

The eighth Moon, august and regal

By the Julian modum viventi

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Still, the Equinox vernal

Drifted steadily toward eternal

Delaying the Resurrection

For each revolution, diurnal

***

Aloysius Lilius

A mathematician imperious

For forty years removed the Leap

Till Easter fell, again, religious

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Gregory XIII, too

In 1582

Declared the way we count our months

In the Janus to Decem queue

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No one knows what happened that year

From October fifth to fifteenth, in arrears

Persons born — then — were simply unborn

In a ten-day Limbo's contrivance engineered

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I spurn and leap, not, the spurious day

Every four years that comes our way

In lieu I take annual six-hour respite

Each Sextilis, led calendrically astray

***

Inspired by https://www.calendar.com/history-of-the-calendar/#:~:text=The%20year%20had%20already%20been,June%2C%20September%2C%20and%20November

The Gregorian calendar was adopted on Friday, October 15, 1582, during the papacy of Gregory XIII. The previous day, according to the Julian calendar, was Thursday, October fourth.