Masonry is very wide spread in France, where it originated.
There is much things said about masonry so I suggest you do some research.
From the very little I know they had acquired much knowledge about architecture, geometry and its influence in our human world. They were building the cathedrals or churches in a specific way to unleash a certain (beneficial) effect on Human. You can note this by entering some magistral churches/cathedrals and be somehow 'lifted' into another dimension.
Its the Science of Macrocosm and Microcosm, how the universe really is a reflection of one another (as above so below).
THEY don't have necessarily ecclesiastical significance, however if you would have a picture to share we could find out more ;)
Also worth mentioning : Freemasonry is also very widespread and although linked to the former, of a complete different nature. Not always with best intention although they like to make us think so.
As per language secularism: France is not so 'traditionalist' like Italy or Austria or parts of Southern Germany (Bavaria). The church is loosing considerably practicants but still very strong.
French people are generally regarded as more emancipated from that point of view so when we are talking about secularism its not much about whether people believe in a faith or not, whether they are practising it by going to church or not, its more about how the sphere and influence of religion (and religious culture) are kept at bay from mingling in politics and everyday social life.
In Rome for instance the Pope has (despite that Italy considers itself laic and secular) much more sphere of influence in politics than in France. Mainly because he is supported by much more institutions / people and for other reasons.
I was surprised of one thing too this year: In France its hard to find mass in smaller villages. Often the mass runs once a week on sunday and that's it. Especially in smaller towns.
Or unless your in Lourdes ;)