**[Shahaji Bhonsle][1] is the biological father of [Chhatrapati Shivaji][2].**  

There are **innumerable sources** for this, two are mentioned below:

1. [Shivaji and His Times][3] by [Sir Jadunath Sarkar][4] 
2.  [Shivaji][5] by [Setu Madhavrao Pagadi][6]

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**Without any facts and evidences**, [James Laine in his book][7] claims a Hindu Brahman scholar and Shivaji's teacher,  [**Dadoji Konddev**][8] as Chhatrapati Shivaji's biological father. **Laine does not calim any Muslim as his father.**
 
Laine cites following source for his assumption: (on page 93 of his [**book**][7].) 

> Maharashtrians tell jokes naughtily suggesting that his guardian
> Dadoji Konddev was his (Shivaji's) biological father.


Now, this book [ does not make any such claims and James Laine has apologized][9] for his mistakes.

**And claiming some Muslim pathan as a father of Chhatrapati Shivaji is nothing but a propaganda to maligning his great image. And all such claims are factless.** 

Shahji was a general and later regent of [Nizamshaha][10], a Muslim ruler in Ahmednagar.  Marathas treated everyone equal and never discriminate on lines of caste and religion. So, Shahji worshiping a Muslim saint or Chhatrapati Shivaji employing Muslims in his army is no surprise. 





  [1]: http://en.wikipedia.org/wiki/Shahaji
  [2]: http://en.wikipedia.org/wiki/Shivaji
  [3]: http://www.amazon.com/Shivaji-His-Times-Jadunath-Sarkar/product-reviews/8125013474
  [4]: http://en.wikipedia.org/wiki/Jadunath_Sarkar
  [5]: http://books.google.co.in/books/about/Shivaji.html?id=_Rcfbh5e1_sC&redir_esc=y
  [6]: http://en.wikipedia.org/wiki/Setu_Madhavrao_Pagdi
  [7]: http://www.amazon.com/Shivaji-Hindu-King-Islamic-India/dp/0195141261
  [8]: https://en.wikipedia.org/wiki/Dadoji_Konddeo
  [9]: http://news.outlookindia.com/items.aspx?artid=217962
  [10]: http://en.wikipedia.org/wiki/Nizam_Shahi_dynasty