1898-July 1900
The construction and the opening of the first Parisian Metro line. The train rumbled through its tunnel not far from the church crypt.

1870-1903
Auguste Gout (1832-1903) became joint pastor in 1870, and in 1873 he became the Leading Pastor in the church. He hoped to build a closer acquaintance with the Lutherans, because the Union of Young People put pressure all at once on the St. Mary's church, and that of Bon-Secours. The liturgical service, chosen by the deceased pastor "with humiliation" for his own funeral on the 29th September 1903, was significant of the fighting evangelical spirit that he incarnated.
From 1899-1903, he was also the President of the Consistory of Paris.

13th December 1903
The church celebrated a century of protestant worship in St. Mary's. The Presbyterian advisor recounted its history.

1902-1913
Elisée Lacheret (1851-1920) became pastor over the parish. His firm evangelical convictions opposed those of Pastor Charles Wagner of the church "Foyer de l'âme, the last liberal church in Paris. He confronted and supported the new-found situation of the vote to separate the church and state of 9th December 1905; and a plaque was placed in the church in 1921 as a reminder of the homage paid to the National synod of Marseille. "In memory of he who consecrated his talents, all the power of his work, his days and his nights to ensure the freest separation possible for all services, and then for organising the Evangelical Reformed Churches."
From 1902 to 1909, the second pastor in the parish was Samuel Diény.

1906
On the 25th February the Presbyterian Association of the Reformed Evangelical Church of St. Mary's was founded.
On the 29th November there was a declaration of the Prefecture of the association of 76 Avenue Ledru-Rollin.

1909-1946
Paul Gounelle (1870-1954) was pastor. He was the son of a Methodist pastor and his three brothers were also pastors (Elie, Edmond and Théodore). Called up in the First World War as a military chaplain in Morocco, he was also chaplain to the Queen of Holland.
He was a firm partisan of evangelical doctrines. From 1927 he was the manager of Christianisme au XXe siècle (Christianity in the XX century), where practically every week he published a meditation. These have been collected in the book Aux sources de Vie, Fischbacher, 1933, and Paroles de Vie, S.E.C., 1956.

1914-1918
There were 99 deaths in the Parish during the Great War. Paul Morel, pastor from 1908-1914, disappeared around the 22nd August 1914 (read his meditations Paroles d'un Jeune, Marseille, 1920). A commemorative plaque for the dead was revealed on the 21st March 1920, with the verse "In God all are alive", Luke 20:38. In 1914 there were 22 deaths, in 1915, 38, in 1916, 15, in 1917, 8, and 1918, 13. As in the Franco-Prussian wars of 1870, the crypt served as a shelter during the bombardments of 1918.

1915-1948
Jules Dejarnac (1877-1952) became pastor. After having been a supplementary pastor from 8th April 1915, he was made the main Pastor in 1919. His ministry lasted for 27 years, in harmony with that of pastor Gounelle. His sermons were always simple, caring, and realistic, with three particularities: temperance &endash; he was president over the Parisian section of the Blue Cross-, justice, and pity. He had an special gift for pastoral visits and also had a complete knowledge of his parish. In 1917 he published a prayer book for children, and in 1927, a brochure entitled "The friend for the ill and the oppressed, a bible guide".

1923-1963
"Fraternité" (brotherhood) was published, the bulletin of St. Mary's church.

Between the two World Wars
The parish was revitalised by the wake-up missions: districts of Bercy and Le Foyer Evangélique of Ledru-Rollin were aware of a new blossoming of faith.

21st June 1931
Wilhelmina, Queen of Holland, and her daughter Juliana, born in 1909, came to the service, which was presided over by pastor Paul Gounelle. Since Pastor Marron, the pastors held the privilege of being chaplains to the Dutch embassy.

1938
The parish of St. Mary entered into the new Reformed Church of France.

3rd December 1802
By the decision of First Consul Bonaparte, the church of St. Mary was changed to host a Reformed Service. Along with the church of Saint Louis of the Louvre (replaced by the Oratory in 1811) and the church of Pentemont, Grenelle road (first service held only in 1846), these three churches were the first to hold reformed services since the revocation of the Edict of Nantes and the destruction of the cathedral of Charenton. Finally, the church of Billettes was given to the Lutherans in 1808. However, the Church of St. Mary is the oldest church in the contemporary history of Parisian Protestantism.

7th March 1803
Prefectorial decision settling the attribution of St. Mary to the protestant Constituency of Paris occurred.

1st and 8th May 1803
The Church of St. Mary was opened on the 1st May, by the Swiss Pastor of Bâle, Frédéric Mestrezat (1760-1807). The "opening prayers" were conducted on the 8th May by the "Ministre Saint-Evangile" and president-pastor of the Constitutional Church of Paris, Paul-Henri Marron (1754-1832): "Glory be to God in heaven! Peace on earth! Goodwill towards men!" (Inscription traced on the vaults of the church building: "Gloria in excelsis Deo et in terra pax hominibus bonae voluntatis", Luke 2.14). In the chapels on either side of the entrance are the bronzed plaster busts of the first Pastors of the protestant church, Marron and Mestrezat.

1805
Rue Castex was built alongside the church, named after Colonel Pierre Castex (1760-1805) of the 13th Infantry regiment, who died in the battle of Austerlitz.

1807
Structural improvements were made to the dilapidated building.

1809
The Interior Minister gave St. Mary's church the organ from the Sceaux Chapel, dating from the XVIII century. It was altered in about 1895, by the House of Merklin, and was made electric in 1928.

12th December 1830
The three first French missionary pastors from the Société des Missions Evangéliques de Paris were sent to South Africa; Prosper Lemue (1804-1870), Issac Bisseux (1808-1896) and Samuel Rolland (1801-1873). They were consecrated in the Church of St. Mary on the 9th May 1950. A plaque was unveiled in the Chancel by the President of the Reformed Church in France, Marc Boegner.

2nd May 1829
National funerals were held for the Politician and writer Benjamin Constant (1767-1830) who died on the 8th December 1830. The young people in the local schools disrupted the ceremony, which was led by Pastor Anthanese Coquerel, crying "Au Panthéon!"

1834
On the church land, the house and gardens of a concierge were established.

6th November 1841
The community of the dioceses of Reuilly, founded by the Evangelical pastor of Paris Antoine Vermeil (1799-1864) and Caroline Malvesin was integrated into that of St. Mary. These dioceses participated in the activities in the parish for over a century.

5th August 1844
A law was passed that conceded the church to the City of Paris.