We all have come across the rhyme "Ringa Ringa Roses" during our kinder garden. Ring a Ring o' Roses" or "Ring Around the Rosie" or "Ring a Ring o' Rosie" is a nursery rhyme. Do you think its a happy song? No, its not.

Current lyrics of this rhyme : (Common British versions)

Ring-a-ring o' roses,
A pocket full of posies,
A-tishoo! A-tishoo!
We all fall down

(But when I was young they thought me as

Ringa Ringa Roses,
Pocket full of poses,
Hush-sha Hush-sha
All fall down.

*Indian version*)

Original lyrics of this rhyme :

(Common American version) 

Ring-a-round the rosie,
A pocket full of posies,
Ashes! Ashes!
We all fall down.

Meaning of this rhyme :

Have you heard about the great Plague of London? The plague of London in 1665 carried away nearly one fifth of the total population in London.

The people who were affected by plague will have round swollen lymph on their bodies.

These people will be segregated from others because this disease can spread through air by the infected droplets. So people hide these lymph by covering them under their clothes. However when the lymph ruptures it gives a foul smell. So to hide that smell they keep poises in their pockets (poise or posy is a flower  producing sweet smell).

Ring shaped round lymph and the poises in their pockets represents the first two lines of this rhyme.

Ring-a-round the rosie,
A pocket full of posies

These affected people will died very soon like within a week. The dead people will  be burnt down to ashes.

The second ashes in the poem represents the ashes due to the great fire of London in 1666.

The great Plague of London and the Great Fire of London were the two national calamities of the Restoration period in 1665 - 1666.

The last line of this rhyme represents the death of the people due to these two calamities. 

So,

Ring-a-round the rosie,
A pocket full of posies,
Ashes! Ashes!
We all fall down.