I also faced this problem, because tableau not recognizing Uk countries
(England, Scotland, Wales, NORTHERN IRELAND).
But I have done this one by small tricky process here are the details what I have done.
- Create a filled map using the Country field and the desired measure.
- Right-click on the country field and duplicate the field. The new field is called "Country (Copy)" in the attached workbook.
- Right click on Country (Copy), go to Geographic Role and select "State/Province". We now have 2 copies of the country field, however, Tableau is reading one as country data and one as a province data.
- Step one will have brought Longitude to Columns and Latitude to Rows, for the next step drag a second copy of latitude to rows, right-click on it and select "Dual Axis". The map should not have changed since step 3.
- Now click on the 2nd instance of Latitude in the Marks card and remove Country.
- Drag Country (Copy) to detail on the Marks card.
- There will be an "Unknown" box in the bottom right corner of the map, click on this, change the Country/Region to United Kingdom and then click OK. All countries should be plotted correctly.