The 1873 marriage of Herbert George Lousada and Marion Helen Mocatta has a Livorno background 

 This chart was compiled originally to show how Herbert George Lousada #206 and Marion Helen Mocatta #207, partners in a 1873 marriage (see notes 2, 3 and 4 below), were related. It can be seen that they had a common ancestor Jacob Baruh Lousada #36 and hence were 3rd cousins once removed; Isaac Lamego was also a common ancestor and from this perspective they were 4th cousins.

 However the chart also shows how the Lousada and Montefiore families were linked in England via Mocatta marriages. This multiple link shows that the English Lousadas, all the English Mocattas descending from Abraham Lumbroso de Matos Mocatta, and all the English Montefiores descending from Mocatta marriages, had a common ancestor Isaac Lamego (see also note 7 below). In fact, the chart shows an even broader pattern - the strong linkage of the Livorno Jewish families once they got to England - Mocattas, Montefiores, Baruch Lousadas and Lumbroso de Matos. The inclusion of Joseph Barrow Montefiore (see note 5 and 8 below) reminds us that the Barrows in Barbados also linked the families, and that this link reflected the first Barrow links with the Baruch Lousadas and the Montefiores which occurred in Livorno in the 1700-40 period.

The chart also shows the connection between Sir Moses Montefiore (see note 1 below) and the Baruch Lousadas, on the one hand, and the Barrow Montefiores, on the other.

Notes:

1. Sir Moses Montefiore is famous for many things - one of which is linked to the Barrow Montefiore presence in Australia. Curiously, he was born in Livorno!

2. Claude Lousada, second son of Herbert George Lousada, and his bride Maude Spielmann were related in a number of ways, but their Ashkenasi link is of interest (see note 5 below). Maude Spielmann was a granddaughter of Sir Joseph Sebag Montefiore, a grandson of Joseph Elias Montefiore.

3. An image of their original marriage contracts can be found here. The father of Herbert George Lousada, George Baruh Lousada, studied architecture under David Alfred Mocatta 1801-1882, who was a grandson of Abraham Lumbroso de Matos Mocatta 1730-1800 via Moses 1768-1857 the oldest surviving son (all these details according to ref 80).

4. Both mothers-in-law were named Juliana leading to the somewhat unconventional naming of Julian George Lousada, their first son. Photographs of Herbert George Lousada and Julian George Lousada can be found in the page dealing with their descendant Sir Anthony Baruh Lousada.

5. This Ashkenasi link involves the Goldsmids who of course figure in the above chart in the form of Juliana Goldsmid. She was a great-granddaughter of Alexander Isaac Keyser who went into partnership in Abraham Lumbroso de Matos Mocatta's bullion-broking firm in 1760 and it was upon his death in 1779 that Asher Goldsmid became a partner in what was then (and now) named Mocatta & Goldsmid. See also note 8 below for further Goldsmid connections.

6. The Mocatta name is of Arabic origin and denotes early residence in Spain (ref 6 p 199).

7. The literature suggests Isaac Lamego's wife Rachel was a Baruch Lousada and our work (see note 14) indicates David #612 of Barbados, oldest brother of Emanuel #41 shown in the chart (top left), was her father. Accordingly Rachel, plus David and his father Aaron of Barbados, are key ancestors also.

8. Daniel Mocatta married Nancy Goldsmid though this marriage is not shown above but their son George accompanied his brother-in-law Joseph Barrow Montefiore to Australia. The Barrows after arriving in England around 1785, played a role in the Ashkenasi linkage (see notes 2 and 5 above), for the mother-in-law of Simon Barrow of Bath was Polly Goldsmid. These additional links are shown in the separate chart of Australian Lousadas and Barrows.