Of him who promises much, much will be expected.

Kinloch's birth date is given as March 7, 1755 across various sources

We begin with the most basic piece of evidence. Several encyclopedias, biographical sites, and ancestry sites give March 7, 1755 as Kinloch's birth date. Kinloch's siblings typically don't have such certainty associated with their birth dates - they often just have a year and perhaps a month given, but rarely (never?) a specific date. The fact that this specific date has been reported across various books and websites with such confidence suggests that there must be some record pointing to this date. But what is it? I've searched some ancestry sites and generally found that the March 7, 1755 date was cited from online biographical entries, but I have yet to find a historical record that gives this date. Birth certificates did not exist in the 18th century, but there were baptismal records, birth/baptism announcements, and even records kept by the families themselves. The Kinloch family history and genealogy research files held by the South Carolina Historical Society mention a Kinloch family Bible that contained the birth and death dates of family members. However, the book was rebound, and some information may have been lost:

The old Kinloch Bible has just been returned by Mrs. Lesesne, whose mother had it. It was left to Grandmama; it was rebound some years before the war, the Green Baize covers being replaced by leather; only one entry of Birth is now in it (see below) but others may have been lost in the rebinding. ... At the top of the blank page between "The Prophets" and "The Apocrypha", is the following in the handwriting of Mrs. Ann I Kinloch. "James Kinloch born at Weehaw near George Town the 11th of August 1762 a quarter before nine at night & privately baptised by the Revd Mr. Prince on the 22d of the same month. Died at Kinsington 12 December 1765 & there buried." (The last in in [sic] lighter ink)

Anne Kinloch was Francis Kinloch's mother, and James Kinloch was his younger brother. Perhaps the Bible previously contained birth dates of others in the Kinloch family, including a potential March 7, 1755 date for Francis. Maybe this information was retained by descendants of the Kinlochs despite it not being retained in the family Bible after its rebinding. Unfortunately, there is likely no way to know what information was lost here. But what else does the Kinloch family have to say?

The Kinloch family history and genealogy research files show much uncertainty about Kinloch's birth date

It is clear from these files that I am not the only one confused about Kinloch's birth date! Across these files, Kinloch's birth date is given as March 6, 7, and 8 with the year given as 1755 and 1756. Often there are cross-outs, numbers written over other numbers, slash marks (e.g., 1755/1756), and question marks surrounding the given dates. If the Kinloch descendants are this unsure of their ancestor's birth date, how can we be confident in the March 7, 1755 date given across various sources? Was March 7, 1755 just picked as Kinloch's birth date at one point and then just parroted across different sources? Again, it's difficult to know the chain of events and passing along of information that happened to give the now-cited March 7, 1755 date. You may be wondering if there are any references to Kinloch's birth date during his lifetime. Thankfully, the answer is yes, but unfortunately, the information is just vague enough to contribute to further uncertainty.

Anne Kinloch mentions Francis's birthday in a 1776 letter

According to a transcript held in the Kinloch family history and genealogy research files, Anne Kinloch wrote the following to her son Francis on March 10, 1776:

Give me leave my dearest much loved Francy to congratulate you on your entrance into your 21st year

This does not specify March 7th as Francis's birth date, but we do get an explicit reference to his age! Unfortunately, this could be interpreted two different ways.

Francis was born in 1755 and turned 21 in 1776.

Francis had just turned 20 in March 1776 and therefore started his 21st year of life, making his birth year 1756.

Francis's 21st birthday would have been a very important one, as he would finally be able to access his late father's estate upon turning 21. It's possible that his mother was congratulating him on reaching this critical age. However, "21st year of life" and "21 years old" are two different things. Essentially, a person turns X years old upon completing their Xth year of life. For example, a newborn is in their first year of life from age 0 days to 365 days, but they do not turn one year old until day 365. The use of "21st year" does suggest a 1756 birth date, but it is possible that Anne was remarking on her son reaching the important age of 21, which suggests a 1755 birth date. Let's see what Francis himself had to say about his age and birth date.

Francis Kinloch stated that he was 56 years old on March 6, 1812

This is the piece of information that makes me believe Kinloch's birth date is either March 7, 1755 or March 6, 1756. @my-deer-friend made a post about a letter Kinloch wrote to his grandson Francis Kinloch Nelson, wherein he mentioned "this day I am 56 years of age." This letter was written on March 6, 1812. @my-deer-friend mentions that the grandson may have mentioned his age in the preceding letter, thus prompting Kinloch's note. According to findagrave, Francis Kinloch Nelson was born March 2, 1800, so it's quite possible that he had made a mention of his age/12th birthday in his letter, thus prompting grandfather Francis Kinloch to mention his age in his reply.

If Francis was 56 years old on March 6, 1812 and was born on March 6, that gives his birth year as 1756. You may think that his solves the whole birthdate issue and pretty firmly establishes Kinloch's birth date as March 6, 1756. Unfortunately, Kinloch was also notoriously a little shit. If March 7, 1755 is the correct birth date, then the date of this letter (March 6, 1812) was the eve of his 57th birthday. I think it's entirely within the realm of possibility that Kinloch confidently stated to his grandson that he was 56 years old at the time of writing this letter, despite him turning 57 in mere hours. This would be technically correct, but very pedantic! Finally, let's come to understand Kinloch's birth through his death.

Kinloch's age at his death on February 8, 1826 is recorded as 69 years

Kinloch died on February 8, 1826, and the "Return of Deaths within the City of Charleston, from 5th to the 12th February 1826" gives his age at death as 69 years. Assuming that Kinloch would have turned 70 on his birthday the following month, this places his birth year as 1756. In Kinloch's obituary authored by his son Frederick, his birth year is again given as 1756. Presumably the Kinloch children would have reported their father's age to the physician who recorded his death as well. This again points pretty clearly to a birth year of 1756, but the obituary does contain a definitive error pertaining to Kinloch's age. It states that he left for England at the age of 9. In reality, Kinloch departed for England in 1768 and would have been 12-13 years old. Did they get both the birth year and the school age wrong? I think it's understandable that children would be less certain about their father's early school years and could have easily made a mistake there, but I think they would have had greater confidence in their father's birth year.

Conclusion: ?