But the migration point gets us part of the way there. It's presented as an ostensible paradox: why does the region with low immigration vote for the anti-migrant party?
The answer is that migration is a two way process. It's not just that eastern Germany is a region of low immigration. Since 1990 it's been a region of massive out-migration, with major demographic effects on who now lives there. So those election maps are telling you about characteristics as much a region.
For one thing, eastern Germany has a skewed ratio of males, and non-working males at that. Any shade of blue in the chart is where the ratio female: male is less than 95 percent, and it's often far less than that. Migration affects quality of life even when it's people leaving than arriving. And people vote on that basis. So a strange conclusion: yes, the election was partly about Mrs Merkel's decision to let in 1 million Syrian migrants. But it's also about decisions nearly 3 decades ago that gave freedom of movement to eastern Germany.