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March birthdays: a dated selection and how calendars shape each date
March birthdays in a celebrity calendar, from Einstein on the 14th to Clapton on the 30th, are civil dates shaped by calendar drift and Pope Gregory XIII's 1582 reform.
March birthdays in a celebrity birthday calendar are civil dates, not positions in the sky. Albert Einstein was born on March 14, 1879; Lady Gaga on March 28, 1986. Both are recorded in the Gregorian calendar, the system this site uses. That calendar was redesigned for one reason: the spring equinox would not stay put.
It also means a date from an old record needs more care than its digits suggest. A celebrity birthday is a civil count, not a fact about the sky. Bruce Willis was born March 19, 1955, and that date is a record, not a natural event.
What to take away
- A birthday calendar records dates in a civil calendar, and any whole-day calendar slowly drifts against the seasons.
- The Gregorian reform corrected that drift by dropping days and changing the leap rule, so that the equinox returned to roughly where it had sat in the fourth century.
- A birthday marks a count of civil days, not a return of the sun to the same place. The two agree closely and never exactly.
Why a calendar drifts at all
The tropical year, from one spring equinox to the next, is not a whole number of days. It is a little under 365.25.
Calendar drift and the 1582 reform
- Julian ruleleap day every four years
- Average year365.25 days, slightly too long
- By 1500sequinox crept about ten days
- 1582 reformdropped accumulated days
- New leap rulecentury years need divisibility by 400
- Average year365.2425 days, drift now slow
A calendar uses whole days, so it approximates. The Julian calendar approximated with a leap day every four years, making its average year exactly 365.25 days. That is slightly too long. The excess is small, about three days in four centuries, but it accumulates one way and never cancels.
Over the centuries, the calendar date of the equinox crept earlier. By the sixteenth century it had moved about ten days from where it stood when Easter's dating rules were fixed.
The reform of 1582 was decreed by Pope Gregory XIII, which is why the result is called the Gregorian calendar. It did two things: it dropped ten accumulated days, so that October 4, 1582 was followed by October 15 in the countries that adopted it first, and it changed the leap rule so century years are leap years only when divisible by 400.
That brought the average year down to 365.2425 days, close enough to the real figure that the remaining drift takes thousands of years to reach a single day.
What the equinox has to do with a birthday
Nothing directly, and that is the point worth keeping. A birthday repeats a date, and a date is a position in a civil count. When a celebrity birthday calendar lists March 14 for Einstein or March 28 for Gaga, it records a civil date, not an astronomical observation.
The March equinox falls on March 19, 20 or 21 depending on the year, because calendar and sun are only roughly in step. Someone born at the equinox was born on a calendar date, and that date returns.
The distinction matters because many claims about birth dates quietly assume the date is a natural fact. It is a recorded one. The same holds for the January birthdays page and for every March entry here, whether Einstein's 14th, Gaga's 28th or Willis's 19th: each is a civil record, not an astronomical observation. For how a modern date is confirmed before publication, see how a US birth date is verified.
March celebrity birthdays: a dated selection
This is a selection, not a full calendar. Each date is a Gregorian civil date as widely published, and every person below was born after the 1582 reform and in a country using the Gregorian calendar, so none needs conversion.
- March 10Jon Hamm (1971)
- March 14Albert Einstein (1879), Michael Caine (1933), Billy Crystal (1948)
- March 19Bruce Willis (1955)
- March 20Spike Lee (1957)
- March 22Reese Witherspoon (1976)
- March 24Jessica Chastain (1977)
- March 25Elton John (1947)
- March 27Quentin Tarantino (1963)
- March 28Lady Gaga (1986)
- March 30Eric Clapton (1945)
For every day of the month, see March birthdays by day and the 2027 planning list. For one profession, see the musicians born in March and athletes born in March pages, and for older dates, historical figures born in March.
Three calendars that mostly agree
Leap rule
- Julian
- Every fourth year, without exception
- Gregorian
- Every fourth year, except century years not divisible by 400
- Revised Julian
- A different century rule with the same practical result for several centuries yet
Where it still shapes dates
- Julian
- Records made before a country switched; some churches' liturgical calendars
- Gregorian
- Civil use almost everywhere
- Revised Julian
- Adopted by a number of Orthodox churches in the twentieth century
The third row earns its place because the Revised Julian calendar matches Gregorian dates now but not forever.
Three calendars, three leap rules
Julian
- Leap rule
- Every fourth year
- Where it shapes dates
- Old records, some liturgies
- Matches Gregorian now?
- No
- Matches Gregorian forever?
- No
Gregorian
- Leap rule
- Except century non-400s
- Where it shapes dates
- Civil use almost everywhere
- Matches Gregorian now?
- Yes
- Matches Gregorian forever?
- Yes
Revised Julian
- Leap rule
- Different century rule
- Where it shapes dates
- Some Orthodox churches
- Matches Gregorian now?
- Yes
- Matches Gregorian forever?
- No
A date recorded under it today is safe to treat as Gregorian, though a converter that assumes they are identical will one day be wrong. Note which calendar a record used, since it costs nothing now.
What this means for March birthday entries
- Modern records need no correction. The drift argument is about which calendar a record was kept in, not about which month it names. Einstein's March 14, 1879, and Gaga's March 28, 1986, are Gregorian dates and need no conversion.
- Records kept under the Julian calendar after 1582 carry a day offset that grew from ten days in 1582 to thirteen by the twentieth century. George Washington's birth, recorded as February 11 at the time, is now marked on February 22; see the historical figures with February birthdays for more such cases.
- The month boundary is a civil line. Two people born in late March share a calendar position and nothing else that a record can show.
- A claim that a birthday falls on the equinox is true of a calendar date in some years and false in others. It is not a stable property of the person.
Common questions
Was the Julian calendar wrong?
It was a good approximation that ran slightly long. Any whole-day calendar is an approximation. The only questions are how fast it drifts and whether anyone corrects it.
Does the Gregorian calendar drift too?
Yes, far more slowly. Its residual error is small enough that no correction has been scheduled, and none will be needed for any date a birthday index will ever hold.
Should a modern index convert old dates from this month?
It should state which calendar each date is in and keep the original wording recoverable. A silent conversion is the one choice that cannot be undone later.
In this guide
- 4 details of musicians with March birthdays people missFour March-born musicians show how a birth date gets fixed, shifted or copied wrong, from Aretha Franklin to Chopin and the clock that moved a day.
- 4 things to weigh up on athletes with March birthdaysAthletes with March birthdays: how an age is set when a birth was never registered, why reported ages round, and how to read a disputed age fairly.
- A closer look at historical figures with March birthdaysMarch birthdays of historical figures run from Michelangelo to Houdini, and each date rests on a verifiable record like a birth certificate.
- Guide to march birthdays by day and what a sort key misses about namesMarch birthdays by day, with the March 1 entries named and the collation rule that decides their order plus the sort key blind spot for name particles.
