According to the Archives of Montre Breguet, construction of the present watch, No. 4230, was begun in June 1823 and finished in June 1825 when it was sold to a Mr. Coutts on behalf of his friend Lord Montfort - "Coutts pour l’ami de Lord Montfort".

This fine and technically superior watch of very high-grade and finish, was sold for the large sum of 2400 Francs in 1825, the price reflected the high cost of making watches with lever escapements, a category of watches described in the archives as being “sur les principes des garde temps" (constructed on the principles of the timekeepers) to distinguish their superior qualities such as precision balance and full jewelling in addition to the lever escapement.

Breguet's elegant ’montres simple’ did not have any other complications to the movement but could have minor additions to the dial, phases of the moon or regulators for example. They were in general made in three categories, "troisième classe", "seconde classe" and, such as the present watch, "première classe", made to the highest standards and with fully jewelled movements, lever escapements and compensation balances.

Few examples of these simple watches with lever escapement have survived and, compared to the number of other types made, their production was limited. Another very similar watch, Breguet No. 4295, was sold to Count Tolstoy in March 1825, also for 2400 Francs.

The designation "Garde Temps" was used only for Breguet's high precision watches, those that were generally made for scientific use. The present watch is fitted with Breguet’s final form of the lever escapement made from 1812 onwards developed for the purpose of enabling Breguet to produce a reliable watch with a close rate for everyday wear. The balance is made of a laminae of steel and a special silver/copper alloy which was apparently invented by Breguet and employed in only his best watches including the perpetuelles. The fully jewelled wheel train is another rare feature at the time even in one of Breguet's watches.

Its case no. 4027 was made by Pierre Benjamin Tavernier, one of Breguet's best early workers and more frequently used by him than any other case maker.

Henry Bromley, 3rdBaron Montfort (1773-1851)
Baron Montfort was a British hereditary title in the Peerage of England. The title expired upon the death of the 3rd Baron, on 30 April 1851. Lord Montfort owned at least one other Breguet watch including No. 3328, a quarter repeater, which he bought on 26 August 1823.

The friend “Coutts” mentioned in the Breguet Archives who collected the present watch for Lord Montfort was perhaps Lord Dudley Coutts Stuart (1803-1854), grandson of the founder of Coutts Bank. Lord Dudley Stuart was the son of Frances Stuart (nee Coutts), Marchioness of Bute, who was also a client of Breguet.

In addition, Lord Dudley Coutts Stuart had married Princess Christine Alexandrine Egypta Bonaparte (1798-1847), daughter of Lucien Bonaparte, Prince of Canino, Napoleon’s younger brother on 20th July 1824. The Bonaparte family being perhaps Breguet’s best customers.