1)  Many secondary sources give our subject the birth date and place of 7 Apr 1787, Natick, Middlesex Co., MA, but this is a different Winthrop COLBATH — son of Winthrop COLBATH, Sr. (1751-1831), & Hannah ROLLINS (1750- ) of Strafford Co., NH.  This Winthrop was born in Rochester, Strafford Co., NH, not Natick; he died in Natick in 10 Feb 1860, which is why he's buried there.  (These dates are apparently from a tombstone in Natick — see source below.)  A relative of this other Winthrop was Vice-President of the United States, which seems to have encouraged people to make a connection to him.

2)  The Nancy STROOPE who married Winthrop COLBATH is said to have been born ca. 1800, the daughter of George H. STROOPE.  The problem is, Winthrop's wife in the 1830 census was a woman in her 40s (i.e., born 1780-90).  Her age is confirmed in the 1840 census where she is in her 50's (i.e., again born 1780-90).  George H. STROOPE was married in March of 1789 (date solidly documented), so it's possible for Nancy to be his first child and, thus, born 1789/90, but we need to revise her birth year.  Nancy's age does raise the question as to whether she is George's daughter.  I have, in fact, found nothing to document Nancy's parentage (or her marriage to Winthrop), at all.  Where does her identity come from?

I will try to find further documentation for this page, but in the meantime, consider this a very tentative first draft.
 

With regard to John's birth date… Dates on tombstones are very reliable for date of death, but very unreliable for the date of birth.  The census records are more contemporary and more first-hand, so are more likely to be correct, especially the earliest one(s).  The parents always know better than the child when and where the child was born — and the grandchildren ordering a tombstone know least of all when and where their deceased parent was born, even assuming the parent was not fibbing about their age later in life (lowering it in middle age and inflating it when elderly).

1.  Marriage Record:

2a.  Census Index:  U.S. Selected Counties, 1810 (Broderbund CD-313):  not found, and there is an Arkansas Territorial census indexed on this CD, but our subject was not listed.

2b.  1810 Census Index/Images (online at Ancestry.com):  not found, and Louisiana records are included, but the Arkansas Territorial census is not indexed here, nor are the images available.

3.  1820 Census Index/Images (online at Ancestry.com):  not found, which means he was presumably in Arkansas Territory because there was no census in 1820 in Arkansas Territory while there was one in Louisiana.

4.  1830 Census Index/Images (online at Ancestry.com; Image #3 of 6; extracted by Diana Gale Matthiesen):¤•

1830

AR

Clark Co.

Caddo Twp.

Roll M19_5

p. 196B

Ln. 5

Winthop Colbath

100 001 100 - 110 200 100

no slaves

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1825-1830	= John (b. ca. 1825)
1 male	30-39	1790-1800	= ?
1 male	40-49	1780-1790	= Winthrop (b. 1784/5)
1 female	4 or under	1825-1830	= Elizabeth (b. 1826/7)
1 female	5-9	1820-1825	= ?
2 females	15-19	1810-1815	= Olive  = Sarah
1 female	40-49	1780-1790	= Nancy

Listed five lines from Jacob STROUPS/STROOPE, Jr. (brother of George H. STROOPE), who is next to Shepherd COLBATH (son of Winthrop).

5.  1840 Census Index/Images (online at Ancestry.com, Image #2-3 of 6 — numerical data pages precede name pages; extracted by Diana Gale Matthiesen):¤•

1840

AR

Union Co.

Pennington Twp.

Roll 20

pp. 228A-228B

Ln. 26

Win Colbreth

000 100 010 - 011 000 010

no slaves

0200000

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	15-19	1820-1825	= John (b. ca. 1825)
1 male	50-59	1780-1790	= Winthrop (b. 1784/5)
1 female	5-9	1830-1835	= Lucinda (b. 1833/4)
1 female	10-14	1825-1830	= Elizabeth (b. 1826/7)
1 female	50-59	1780-1790	= Nancy
1	person employed in agriculture

6.  1850 Census Index/Images (online at Ancestry.com; Image #15 of 52):  Bastrop Co., TX, Roll M432_908, p. 159, 108/114, enumerated 3 Sep 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):¤•

Winthrop Culbreath	65	M		Blk Smith		Mass
John P Stroop	22	M				Arks
Elizabeth Linewever	23	F				"
Lucinda Culbreath	16	F				"
George Linewever	26	M		Blk Smith		Germany

Elizabeth is Winthrop's married daughter, and George LEINNEWEBER is her husband — after Elizabeth's death, George married Lucinda.  Listed next to Winthrop's widowed son-in-law, Henry STROOPE.  John P. STROOPE is Henry's brother.

7.  1860 Census Index/Images (online at Ancestry.com, Image #2 of 10):  Grape Creek P.O., Precinct No. IV, Gillespie Co., TX, Roll Roll M653_1295, p. 27A, PN 53, 442/427, enumerated 28 Jul 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):¤•

Neel Javier	26	M		farmer		900	Arkansas
____ Louise	25	F					"
____ William	5	M					Texas
____ Elizabeth	3	F					"
____ Henry	3/12	M					"
Colbath Winthrop	74	M					Massachusett	blind

Listed next to Winthrop's son, John COLBATH (æ 36, b. AR) and his  wife, Martha (æ 27, b. AR).  Some have taken this record to mean that Louise is Winthrop's daughter, but there is no sign of Louise in Winthrop's household in either the 1850 or 1840 censuses.  More likely Xavier is Martha (NEEL) COLBATH's brother and, for whatever reason (bigger house?), Winthrop is living with him, rather than next door with his son.

8.  1870 Census Every-Name-Index/Images (online at Ancestry.com):  not found.

9.  Ronald V. Jackson.  1999.  Arkansas Census, 1819-70.  Accelerated Indexing Systems (online at Ancestry.com):

1828 Tax List	AR	Clark Co.	Caddo Twp.	Winthrop COLBATH
1830 Tax List	AR	Clark Co.	Caddo Twp.	Winthrop COLBATH
1832 Tax List	AR	Clark Co.	Caddo Twp.	Winthrop COLBATH

10.  Thomas W. Baldwin.  1910.  Vital Records of Natick, Massachusetts, to the Year, 1850.  Stanhope Press, F.H. Gilson Co., Boston, MA (online at the NEHGS):

COLBATH Winthrop	Apr. 7, 1787	G.R.1.	Birth	Natick
G.R. = Gravestone Record; 1. = Dell Park Cemetery

This record is very misleading because it implies Winthrop was born in Natick, which he was not.  He was born in Rochester, Strafford Co., NH.  He died in Natick, on 10 Feb 1860, which is why he's buried there.