Expatriate your prejudice
How I understand it:
That row is about character, and as we go along we arrive to the Hungarian, where it says
>most gruesome
Then we arrive to the Russian, which says:
>good Hungarian
So a Russian's character is like a good Hungarian's - who is the most gruesome...
I believe whoever authored the image, he did not lack humour.
> Could you still read and understand a Hungarian book that was written in say 1730?
An 1730? Perfectly. Would sound archaic, but would case no problem.
Our oldest language fragment written with Latin letters is from the 11th century. An average IQ Hungarian with average literacy could understand it, even tho he would find it strange.
Lemme quote it, and in modern Hungarian:
>feheruuary rea meneh hodu utu rea
>Fehérvárra menő hadi útra
Perhaps among the first thing to notice that "rea" became "-ra" suffix joined to the word.
Another thing that in the old text there are no: é, á, ő, ú letters. So for example the author used "eh" to scribe "ő" (long ö sound), or the "ea" stood in place of the "á".
BUT. You have to consider that the line above was written with a foreign alphabet and there were no rules of writing the spoken language yet! The customs and conventions were formed during the centuries but the normalization started extremely late just about the time of your example. We used Latin with some additional German later on when it came to official business, and teaching happened in Latin, so noone were thinking about "how would we go about writing Hungarian sounds with Latin letters". The sounds we use already existed, but not the letters.
But we had earlier writing system, the "rovásírás" (cca. Hungarian runes) which at least had proper letters for all the sounds. There were no rules of grammar to regulate those texts written in that script however, and they often used "ligatures", combination of runes, often leaving vowels out, so it is a bit chore to "decode" those.
There were some phonetical changes throughout the centuries, and some dialects became more prominent, others disappeared (we still have some, preserving archaic forms).
The Hungarian language reform happened about the century between 1770 and 1870, the core of the work done about 1790-1820. So basically about the same time where everywhere else. They aimed to create a "normalized" language, with described grammar and Hungarian words. There were many Germanism to get rid of (and surprisingly they kept the German custom of compound words), and ofc plethora Latin and Greek words that needed to be replaced in common and literary use (they still remained as scholarship, erudition, and for certain professions - most notably medicine and law). They created new Hungarian words (sometimes they just had to add affixes and suffixes), used translations for foreign ones, but most of the time they dusted off archaic ones or popularized words from dialects.
That's about it.
From the top of my head I'm not sure how/when they changed the language used in schools.
Not sure. It's not easy to differentiate between Hungarian findings and the rest of the steppe people's and all had their own runic writings, Turkic people, Huns, Sarmatians, Scythians, and the rest. Hard to tell apart. So getting further than the 10th century AD is impossible.
Supposedly Hungarian language separated like 3000 years ago, but as with languages usual, all evidence is theoretical with some level of mental gymnastics.
Heh even with the recognized Hungarian runic inscriptions the researchers put forward several solutions what those say.
So to put a date on, things are intelligible to the times Hungarians arrived into the Carpathian basin so about 900 AD. From here we can assume the case would be similar couple hundred years back, or even further.