The process of visualizing France's salary data using region maps in Kibana involves importing a Kaggle dataset on employment, salaries, and population, which is sourced from the French National Institute of Statistics and Economic Studies (INSEE). The data requires preparation by joining tables from different CSV files using SQLite to normalize INSEE codes before importing into Elasticsearch. Afterward, Logstash is configured to ingest this data into Elasticsearch, employing CSV filters to convert and format the data appropriately. In Kibana, a new index pattern is created to visualize salary data by French departments, allowing users to map average mean net salaries across regions and explore gender pay gaps through scripted fields. The visualization process involves customizing region maps to display data layers such as department name and salary ratios, providing insights into salary distributions and disparities across different demographics in France.