The inventory, and who held it
When two households merged, who owned what the other had brought in — and whether that even had an answer — depended entirely on where you lived and when.

The inventory itself
Before a marriage, a careful family drew up a list. The bride's linens, her mother's silver spoon, a feather bed, a named sum in coin — all of it itemised, often in front of witnesses, sometimes lodged with a notary. The groom's side might produce a corresponding statement of what he held in land, livestock or trade. These documents went by different names in different countries: état de biens in French legal tradition, Heiratsgut in German-speaking territories, dote in Spanish and Italian practice. The English equivalent, less ceremonious, was simply the marriage settlement or the jointure deed, drawn up by a solicitor when the parties were prosperous enough to bother.
The inventory served two purposes at once. It was a record and a claim — proof that certain things had entered the marriage from one side, so that their origin could, in theory, be traced if it ever mattered. And it often mattered enormously.

What law made of property brought in
The critical question was whether a woman's goods survived the marriage as a distinct legal category, or dissolved into what her husband held. Under English common law until the late nineteenth century, the doctrine of coverture swallowed a wife's personal property the moment she married. Moveable goods she had owned became his; debts she owed became his to settle; money she earned belonged to him. The inventory still existed, but it described things that were now, legally, in his hands. Only the Married Women's Property Act of 1870, followed by the fuller Act of 1882, gave an English wife the right to hold property separately and in her own name.
Continental systems were not uniform. Many French regions before and after the Revolution operated a communauté de biens — a community-of-goods arrangement — under which property brought into the marriage pooled into a joint estate, managed by the husband but shared in ownership. Specific items listed on the inventory, however, were sometimes carved out as the wife's propres, meaning her own, and were expected to return to her family of origin at her death rather than pass through her husband's line. This distinction between the pool and the reserved items was precise, litigated and financially serious.
German territorial law varied city by city, but many jurisdictions recognised the Errungenschaftsgemeinschaft — a community limited to what the couple had acquired together — leaving what each had brought in still technically separate. Spanish law maintained a similar distinction between bienes gananciales (jointly acquired) and bienes propios (each spouse's own prior property), a framework that survives in modified form in Spanish civil law today.
Moveable goods she had owned became his; debts she owed became his to settle; money she earned belonged to him.
In Scotland, where neither English common law nor Continental civil codes applied directly, married women retained somewhat stronger property rights than their English counterparts for much of the early modern period, a difference that matters when reading the records of families who straddled the border.

Who actually held the document
The physical inventory, wherever it was kept, was a form of power. A woman whose family had lodged a copy with a notary had recourse that a woman who had handed everything over informally did not. The document testified to what she had brought; without it, the burden of proof in any dispute fell on her.
Widowhood was the moment the inventory became urgent. In many jurisdictions a widow was entitled to the return of her dower or her dowry portion — the goods and values listed at the start. Whether she received them depended on whether the list survived, whether her husband had kept the assets intact, and whether anyone in the household could be made to account for what had gone. What the chest held had always been about evidence as much as comfort: the linen in the inventory, the spoon with the initialled handle, was there to be counted again when counting became necessary.

The inventory was, in the end, a hedge against optimism — a quiet acknowledgment that not all marriages outlasted the people in them, and that the record of what each had brought might one day be the only way to untangle what each was owed.