STEMMA History

Development of the STEMMA® ("Source Text for Event and Ménage MApping”) data model and source format began around 2011. This page charts its chronological history.

Draft [2012-01-02]


First draft specification uploaded to new STEMMA Web site.

Draft [2012-04-27]

The STEMMA research notes were collected together and made (almost) readable. The 70+ pages were uploaded to the STEMMA site as a resource for any similar work on family history data to utilise.

V1.0 [2012-07-16]

STEMMA passed from being a draft specification to the first fully working version.

A number of its features were streamlined or revised as a result of it being applied to my own data, and following further research. The copious associated Research Notes were updated in keeping with the new specification, and supplemented by a Data Model section that shows the model being applied to a number of case studies.

New or improved features include:



V2.0 [2013-05-28]


STEMMA underwent a considerable number of refinements to both strengthen and streamline its specification. Features include:



V2.1 [2013-10-16]


Changes include:



V2.2 [2014-04-17]


Changes include:




V3.0 [2014-10-20]


Major change to trim excess flexibility, and to address certain known failings:



Changes include:




V4.0 [2015-11-22]


Major change to finally accommodate sources, information, evidence, and conclusions in a single model that supports the major approaches to research and representation.


Changes include:



Although refinements will continue, I anticipate this to be the last major change to the STEMMA specification. I will, therefore, concentrate subsequent efforts on describing its advantages and philosophy, and in providing more worked examples.



V4.1 [2017-04-19]


Refinements to STEMMA specification, especially in the areas of transcription (multiple contributors, audio, and linking to images or recordings) and narrative mark-up (tabulated data, and citations).


Employment of the revised narrative support may be viewed in the fully-worked examples at: and


V4.1 still [2020-12-10]


Canonical URL changed to following a move from Google Sites to The previous URLs (,, and will be redirected to the new URL.

V4.1 still [2024-01-01]


At the end of 2020, the public version of the STEMMA specification was fixed at V4.1, although a number of small changes in specification and direction have occurred internally for private usage. Little work has taken place on the informational sub-model that was to support a dynamic research process, but a spin-off of the associated experimentation was the SVG Family-Tree Generator (SVG-FTG) that is now a separate product. Work has focused, instead, on the conclusional sub-model (see STEMMA Latest). Since that time, GEDCOM v7.0 has been defined, but STEMMA remains in a niche of its own.