Chiefly correspondence between Captain Dudley Avery and his wife, Mary Ann Browne Avery. Between 1814 and 1816, Dudley Avery wrote numerous letters to Mary Ann from New Orleans where he was apparently serving in the legislature. In his letters of 1814, he mentioned General Jackson, the progress of the War of 1812, and some of the discussions in the legislature. He also wrote of acquiring items for his family in New Orleans and efforts to recover a runaway slave. In December 1814, Avery wrote about the troops that were in New Orleans, expectations of attack, and later, two battles that had taken place. He served as a medical officer in a regiment of Drafted Militia during the Battle of New Orleans and continued to wrote several accounts of the conflict. Dudley Avery's last letter, dated June 1816, is headed "Schooner Industry, Belize." A letter from September 1816 refers to Avery's death. Also included are a few scattered papers of John C. Marsh, who had not yet left New Jersey.

Correspondence shows that John C. Marsh was settled on Petite Anse Island by the fall of 1818 with his brother Stewart following a few months later. Marsh's wife Eliza and his partner William Stone joined them in 1819. Materials in this subseries are chiefly bills of sale for slaves and indentures executed by Marsh and Stone. Some of the bills of sale for slaves include a form, signed by the slave, agreeing to move to Louisiana. Such forms apparently reflect complications Stone encountered with authorities in New Jersey. John C. Marsh received a letter from Jesse McCall, his overseer who appears to have been operating the plantation in Marsh's absence, in the summer of 1818 about money and supplies.

Other letters between 1818 and 1827 are to Marsh from relatives in New York and New Jersey. Subjects include Marsh's appointment as magistrate, the purchase of slaves, and family illnesses and the death of Marsh's mother. Letters also show that William Stone died sometime in 1826 or 1827.

Materials relating to John C. Marsh and Petite Anse Island Plantation after the death of William Stone. In 1828, Marsh married Euphemia Craig, William Stone's widow. He wrote and received letters about plantation operations and also received a few letters from New Jersey relatives about family matters. Also included in this subseries are plantation accounts, 1826-1828, with numerous entries relating to salt production. There are also notes and documents about the settlement of William Stone's estate. A few documents relating to Daniel Dudley Avery appear. In 1828, Avery entered Yale College from which he wrote to his aunt in Groton. Documents show that he returned to Baton Rouge after graduation in 1832 and was admitted to the Louisiana Bar in 1832.

In 1836, George Marsh, John C. Marsh's son, evidently moved to Petite Anse Island Plantation and began assisting in its management. In 1836, he received a letter from Anthony Marsh in Rahway, N.J., congratulating him on the success of the "first enterprise on your plantation" and describing the poor quality of the crop in New Jersey, a serious fire at Brook and Market Streets in New York, and the rapid growth of Rahway, including the coming of iron factories to the area. During the 1840s, John C. Marsh spent an increasing amount of time in New York and New Jersey, leaving the management of the plantation to George. Much correspondence between father and son about plantation affairs was generated by this separation. There are also letters to George from other family members, mostly about family news. Also included are bills of sale for slaves, a certificate of John Marsh stating that a mulatto man who had been his servant had served his term, and the record of a $4,800 mortgage held by the Union Bank of St. Louis against Marsh. There are also four love letters dated 1837 from Daniel Dudley Avery to Sarah Craig Marsh. The couple married on 17 August 1837.

Chiefly letters from Daniel Dudley Avery to his wife Sarah Craig Marsh Avery while he was serving in the Louisiana state legislature and she was at the Petite Anse Island Plantation with her children. Letters discuss family matters, epidemics, deaths of friends, runaway slaves, and New Orleans social life.

In 1849, John C. Marsh sold one-third interest in the Petite Anse Island Plantation to Daniel Dudley Avery and anther third to Ashbel Burnham Henshaw, husband of Marsh's second daughter Margaret. George Marsh retained one-third interest. Document in this subseries are chiefly fianancial items relating to the plantation under the three-way partnership. In 1854, Avery bought out Henshaw and controlled a two-thirds interest. Included are mortgages; itemized accounts and bills, some of which relate to medical treatment for slaves; a jail fee for a runaway slave; and detailed records from the wholesale brokerage firm of Bogart, Foley, and Avery for marketing sugar and molasses. From 1850 to 1855, accounts show luxury items purchased in New Orleans and shipped to the plantation.

Papers also include tax receipts, promissory notes, accounts for wages paid to skilled laborers, and accounts for insurance, freight, and drayage. A document dated 1854 shows the terms of purchase under which Daniel Dudley Avery secured Henshaw's interest in the plantation for $40,000. According to an April 1854 document, John C. Marsh forgave at his death the $31,825 still owed to him by Daniel Dudley Avery. A May 1856 document shows that Marsh freed several mulatto slaves in accordance with an agreement made with their fathers.

Marsh died in April 1857, apparently in Baton Rouge. In September 1859, Daniel Dudley Avery took his son Dudley to Princeton. Young Avery placed in the sophomore class. On this journey, Avery wrote to George Marsh giving him detailed insttructions for handling plantation operations. George Marsh died in December 1859, and various items relate to the settlement of his estate.

Documents relating to Petite Anse Island Plantation and Avery family of Louisiana members during the Civil War. Included are a few 1862 letters relating to salt production.

John Marsh Avery, second son of Daniel Dudley Avery, secured a temporary deferment from military service in September 1862 to remain on the plantation to supervise salt mining. Also in 1862, the State Geologist of Mississippi conducted an analysis of the rock salt from the plantation. In June 1864, Lt. Dudley Avery wrote to Major-General R. Taylor to secure a deferment for the overseer of the plantation so that he could continue to raise crops and mine salt.

There is little family correspondence for the war years. Daniel Dudley Avery took his wife and daughters to Houston, Tex., in the spring of 1863 and did not return to New Iberia until April 1865. Documents show that in Houston Avery was associated in some type of business venture involving C. S. Longcope, formerly of New Iberia, who corresponded with Avery after his return to Louisiana. John Marsh Avery served as an ordnance officer in the Confederate army during 1864 and 1865. There are numerous ordnance requisitions bearing his signature.

Other documents include promissory notes relating to George Marsh's estate; tax receipts; clothing bills; canceled checks; and salt accounts. In June 1863, Sarah Avery received a letter from an old friend in New Orleans about the gaiety of the city and the return of soldiers. She also heard from a friend in Houston, telling of local conditions after the Averys' departure, including the desertion of the former slaves and the plight of the planters. Also included is a copy of Daniel Dudley Avery's plea for amnesty and a printed copy of President Johnson's Amesty Proclamation of 1865.

Documents relating to the fortunes of the Averys after the Civil War. The chief topic in the years immediately following the war was the salt mines on Petite Anse Island and the family's attempts to make a successful enterprise from salt mining. According to geological reports, the salt deposit was extremely valuable, but correspondence indicates the difficulty the Averys had in obtaining capital to mine the salt and the growing indebtedness of family members.

Following their return from Texas, Daniel Dudley Avery and his family took up permanent residence at the plantation on Petite Anse Island, which came to be known as Avery Island. Edmund and Mary Elizabeth Avery McIlhenny also lived on the island. In 1866, there are letters to Daniel Dudley Avery in New Orleans from his son John Marsh Avery, who was apparently managing the plantation in his father's absence. John wrote about crops and about clothing to be bought for former slaves, many of whom had returned to work the plantation. A few letters in 1866 discuss the workers' dissatisfaction and attempts to devise acceptable contracts.

In 1866 and 1867, there are numerous letters to Daniel Dudley Avery about the salt mines and efforts to resume production. Other business letters about Avery's financial affairs and about George Marsh's estate are also included. In July 1867, Daniel Dudley Avery received a letter from his nephew R. M. Walsh of Baton Rouge about financial matters and stating that "Negroes [were] registering very rapidly and have their candidates for Mayor, etc." In 1868, John Marsh Avery spent some time in New Orleans where he enjoyed an active social life. He also undertook some business activities for his father.

After 1870, there are fewer business letters to Daniel Dudley Avery and more family letters. Avery and John went to St. Louis, Mich., in 1870 to "take the Water" and wrote home describing Saginaw, where they may have been investigating a saw mill. John Marsh Avery corresponded with his friend Daniel Thompson of Chicago about the Chicago fire. Several letters in 1872 reveal John and Dudley Avery's growing interest in Louisiana politics. Also in 1872, there are letters about the drought, when cisterns ran dry and water was sold on the streets of New Iberia. In Setpember 1872, Dudley Avery wrote to his father in St. Louis, Mich., about his appointment as Police Juror and his election as "chairman of the Parish Executive committee of the Liberal Party, a position of some power and responsibility."

From January 1873 through December 1876, the Averys were involved in a legal battle to retain their property. Daniel Dudley Avery was in debt to the estate of David Hayes with mortgage notes due in January 1873. Avery was unable to raise the money to pay these notes and Sarah Marsh Avery obtained a judgement against him in 1876 to protect her part of the property. Petite Anse was sold at auction in 1876, with a friend buying it at a very low price. The friend then sold the plantation back to the Averys, who were able to retain control of the property.

Sarah Marsh Avery died suddenly in April 1878, and Daniel Dudley Avery received a note of sympathy from actor Joe Jefferson. Daniel Dudley Avery's death is noted in a letter of sympathy to John Marsh Avery dated 11 June 1879.

Documents reflecting some of the activities of the Avery children. John Marsh Avery served on the Democratic Central Committee in New Orleans. There is also Sarah Avery Leeds's correspondence with the Bishop of Louisiana (Episcopal) about religious matters and a letter to Paul B. Leeds fom John C. Caton of Chicago informing him of a scheme of the Morton Salt Company to ruin the reputation of Avery Island salt.

John Marsh Avery corresponded in 1890 with Senator R. L. Gibson in Washington about the coming election, the lottery, the African-American vote, and concern over what he terms the "Africanization" of Louisiana. They also discussed the fact that the levees were down and Gibson's efforts to secure an appropriation for their reconstruction before the floods came.

In 1890, Dudley Avery received a note from Joe Jefferson about a performance of Sheridan's The Rivals given in New Orleans. In April 1891, the Avery family received letters of condolence on the death of John Marsh Avery. In 1892, Sarah Avery Leeds received two letters from Homer D. L. Sweet about a family history he was compiling. She also received a letter from Frances Cleveland, wife of Grover Cleveland, thanking her for a baby blanket, and a letter from Cleveland himself.

In 1895, Dudley Avery wrote to Sarah Avery Leeds about a property dispute, this time with Myles and Company, a salt concern. Also in that year, Dudley Avery wrote a history of the salt mines.

There are only a few items after 1895. Among these is part of a history of Petite Anse Island, including Marsh and Avery family history that was written by Senator Joseph S. Clark in 1951.

Chiefly undated accounts, but also a few letters, including two to John Marsh Avery from R. L. Gibson.